LISTADO CON LAS ABREVIATURAS MAS UTILIZADAS EN AUTOMOCION, UTILIZADAS EN ESQUEMAS, DIAGRAMAS, INFORMACIONES TECNICAS....

OS DEJO ESTE LISTADO CON LAS ABREVIATURAS MAS UTILIZADAS EN AUTOMOCION MUY UTIL A LA HORA DE COMPRENDER Y ESTUDIAR DIAGRAMAS, ESQUEMAS ELECTRICOS, MANUALES, TUTORIALES, NOTAS TECNICAS, INTERPRETACION DE CODIGOS DE AVERIA, DTC,  Y OTROS DOCUMENTOS RELACIONADOS CON EL MUNDO DE LA AUTOMOCION Y LA ELECTRO MECANICA 

ABREVIATURAS  UTILIZADAS EN AUTOMOCION

/MIN	Per minute, usually RPM, physical unit
°C	Degrees Celsius, physical unit
°DK	Degrees throttle-valve angle, physical unit
°F	Degrees Fahrenheit, physical unit
°KW	Degrees crankshaft, physical unit
°NW	Degrees camshaft, physical unit
1/CM3	1/cm³, per cubic centimeter, unit
1L	Axle 1 (usually front axle), left side
1R	Axle 1 (usually front axle), right side
2L	Axle 2, left side
2R	Axle 2, right side
2WD	2-wheel drive
3L	Axle 3, left side
3R	Axle 3, right side
4WAS	Four wheel anti skid, traction control system for four-wheel drive vehicles, refer also to ASR
4WD	4-wheel drive
4WS	Four-wheel steering. All 4 wheels are steered, not just the front wheels.
4X4	Vehicle with 4 wheels, all of which are driven (all-wheel drive). See also 4WD.
A	Ampere, physical unit, or Austria
A/D	Analog/digital, usually A/D converter: converts analog signals (such as speed  or oxygen sensor  voltage) to digital signals that can be processed by a computer
A1	Axle 1, usually front axle
A2/3	Axles 2/3, rear axle(s)
AA	Automatically triggered alarm
AAC	Auxiliary-air control valve
AAP	Acceleration auxiliary pump
AAS	Drive-off assistant
AAV	Activated charcoal filter shutoff valve
AB	Airbag, usually proper name
ABC	Active body control, chassis, see also ADS
ABD	Automatic braking differential, usually proper name
ABE	General operating licence, model approval of car for operation on public roads
ABS	Anti-Blocking System, usually proper name
ABS 2	Anti-Blocking System separate, system name, proper name
ABS 3	Anti-Blocking System integrated in brake booster, system name, proper name
ABV	Auxiliary-air valve or Automatic blocking prevention, another term for ABS
AC	Air conditioning, air conditioner, or Alternating current
ACC	Adaptive cruise control
ACD ACM	Active centre differential, automatic limited-slip differential (Mitsubishi) Airbag Control Module
ACT	Air charge temperature. Temperature of charge air with turbocharger.
ADA	Atmospheric-pressure dependent full-load stop with distributor injection pumps
ADAM	Advanced dynamic aid mechanism, mechanical braking assistant (Teves). See also BAS.
ADAPT	Adaptation, adaption
ADB	Automatic differential brake. BMW system replacing conventional limited-slip differentials  (ensures traction by braking wheels). Subfunction of DSC (BMW ESP).
ADF	Atmospheric pressure sensor
ADN	Yemen
ADR	Automatic distance control, proper name (VW), or Trigger duration control
ADS	Automatic throttle-valve actuator or Active driving system or Adaptive damping system
AEI	Advance electronic ignition, fully electronic ignition system
AEU	Outside Europe
AFB	Atmospheric-pressure dependent start-of-delivery
AFI	Air-supported fuel injection
AFS	Advanced front-lighting system. Variable light distribution via movable reflectors
AG	Automatic transmission
AGN	Exhaust-gas aftertreatment
AGR	Exhaust-gas recirculation
AGRV	Exhaust-gas recirculation valve
AHK AHM	Trailer coupling, or Active rear-axle kinematics Auxilliary Heater Module
AHS	Alcohol sensor
AHV	Trailer brake valve
AI	Air injection
AICC	Autonomous intelligent cruise control (speed and distance)
AIV	Air injection valve
AK	Automatic clutch. Clutch operates when driving off, shifting, and stopping.
AKEK	Automatic child-seat detection, usually integrated into an airbag system
AKF	Activated charcoal filter
AKS	Automatic clutch system. Clutch engagement/disengagement is automatic.  The clutch pedal is no longer needed. Used for example in Renault  Twingo; see also EKS, or Active  headrest system (BMW)
AKSE	Automatic child-seat detection
AKT	Active, or Current
ALB	Automatic load-dependent braking force control
ALC	Adaptive light control. The headlight illumination is distributed variably according  to the driving  situation (city, country, motorway). (BMW)
ALDA	Absolute measurement, boost-pressure dependent full-load stop
ALDL	Assembly Line Diagnostic Link, Opel diagnostic plug
ALFB	Atmospheric pressure and load-dependent start-of-delivery
ALG	Axle load sensor
ALR	Automatic longitudinal control
ALU	Arithmetic and logic unit (microcomputer), proper name
ALV	Axle load distribution (drive-off aid)
ALWR	Automatic headlight vertical aim control
AM	Central America
AMIC	Automotive Multimedia Interface Collaboration, Gremium zur Entwicklung eines Ç Multimediastandards, besteht im wesentlichen aus führenden Automobilherstellern
AMR	Drive torque control
ANC	Active noise control. System actively influences the intake noise, reducing it by about 15 dB.
AND AOS	Logical AND operator Automatic Ocupant Sensing
AP	Air pump
APB	Active parking brake. Teves system containing interface to electronics,  with driver-assistance functions such as drive-off assistance, parking aid, and immobilizer.
APS	Autopilot system
ARA	Anti-jerking control
ARD	Active jerking suppression
ARF	Exhaust-gas recirculation
ARFR	Exhaust-gas recirculation rate
ARMADA	Triggering unit for restraint systems with external differentiated triggering. Airbag system  from DaimlerChrysler.
ARMIN	Trigger unit for restraint systems with integrated emergency-call control
ARR	Exhaust-gas recirculation control
ART	Distance-based cruise control
AS	Air intake or Towing protection or South America
ASC	Automatic stability control, controlled force transmission
ASC+T	Automatic stability control, regulated force transmission with traction control
ASD	Automatic limited-slip differential, usually proper name
ASF	Audi Space Frame, special construction for aluminium frame in Audi A2 and A8
ASG	Attachment control unit or Semi-automatic transmission
ASM ASM	Asynchronous machine Alarm Siren Module
ASMS	Automatic stability management system. See also ESP.
AS-NO	Exhaust-gas sensor for NOx (nitrogen oxide) content
ASP	Shutoff valve for ASR brake control
ASR	Transmission slip control, usually proper name
ASR 2	Transmission slip control, separate, system name, proper name
ASR 3	Transmission slip control, integrated, system name, proper name
AS-T	Exhaust-gas sensor for temperature
ASV	Air switching valve, air intake valve or Trailer control valve
AT	Automatic transmission
ATB	Exhaust-gas temperature limitation
ATF	Exhaust-gas temperature sensor or Automatic transmission fluid
ATG	Replacement transmission
ATL	Exhaust-gas turbocharger
ATWS	Anti-theft warning system (Opel)
AU	Exhaust-gas inspection
AUS AUS	Australia Ultrasonic Alarm System
AUT	Automatic transmission
AV	Outlet valve or Shutoff valve
AW	Drive shaft
AWG	Evaluation switching unit
AWK	Spare piston, used if proper piston does not function
AWN	ASA Workshop Network, proper name
AWR	Distance warning radar
AWS	Evaluation switching unit (Bosch KH)
AY	Lateral acceleration. A=acceleration, Y=lateral direction
AYC	Active yaw control. Rear-axle limited-slip differential (Mitsubishi). See also ACD.
AZG	Adaptive cylinder equalisation. Quantity equalisation control.
B	Internal combustion engine (petrol) or Bank or Belgium
B-	Battery negative voltage
B.C.D.D.	Vacuum controlled idle air correction
B.P.T.	Pressure control valve
B+	Battery positive voltage
BA	Acceleration sensor or Brake assistant (Mercedes Benz)
BAR	bar, physical unit
BAS	Brake assistant system
BBA	Service brake system. Enables the driver to reduce the speed of a vehicle in steps  during operation (including to standstill). In addition to the service brake system,  a vehicle can have a parking brake, a retarder system, or an auxiliary braking system.  A service brake system can be a single- or multiple-circuit system and can  work mechanically,  hydraulically, or pneumatically.
BBR BBUS	Wideband noise test, method for testing potentiometers Body Bus
BBV	Service-brake valve. Component of service brake system. See also BBA.
BC	Blink code
BCM	Body control module (Opel and GM)
BD	Bd: baud. Unit for data transmission rate. 1 baud is 1 bit/second.
BDE	Petrol direct injection
BDM	Petrol/diesel speed measurement module
BEA	Bosch Emissions Analysis, product name for exhaust-gas tester (Bosch)
BEV	Battery electric vehicle
BF	Passenger, or passenger-side
BFA	Passenger airbag. See also BF-AB.
BF-AB	Passenger airbag
BFL	Brake fluid level
BFS	Passenger side
BG	Brake assembly, integrated ABS, or Bulgaria
BHKZ	Battery high voltage capacitor ignition
BIP	Start pulse
BKL	Brake indicator light
BKR	Braking force control
BKU	Braking force support
BKV	Power brakes
BLDC	Brushless direct current motor
BLS	Brake light switch
BLU	Brake light suppression. Activated when the brake assistant carries out a "preliminary charge".  The main brake cylinder is actuated, leading to actuation of the light switch. Since the driver  has not braked, switch-on of the brake light must be suppressed
BM	Reference mark
BMR	Braking torque control
BOU	Brake operating unit, controls and activates the brakes
BPA	Start of paraffin precipitation. Also called cloud point. Temperature at which paraffin crystals  precipitate out of diesel fuel.
BPS	Brake test stand
BR	Brake control for ASR or Brazil
BRP	Wideband noise test, method for testing potentiometers
BS	Brake disc or Acceleration sensor
BSA	Brake system analysis, product name for brake test stand (Bosch)
BSU	Special brake inspection
BT	Brake drum
BTC	Bosch traffic controller, traffic monitoring system
BTS	Battery disconnect switch (Mercedes)
BV	Brake valve
BVA	Brake wear indicator
BVSV	Bimetallic-controlled vacuum switching valve or Bimetallic vacuum switching valve
BWN	Bosch Workshop Network, proper name
BZ	Brake cylinder
BZM	Reference mark
BZW	respectively, or, and/or
C	Capacitor, capacitance, or Chassis (OBD error codes, for example) or Cuba
C.R.	Compression ratio
C3/B7	C3/B7 signal (speed signal for trip recorder)
CAA	Clean Air Act (US exhaust-gas regulations)
CAL	California
CAN CANDI	Controller Area Network, mini-network for exchanging data between computers,  proper name Can Diagnostic Interface
CAN-H	CAN High. One of the two data lines in the CAN bus system. See also CAN.
CAN-HI	CAN High. One of the two data lines in the CAN bus system. See also CAN.
CAN-L	CAN Low. One of the two data lines in the CAN bus system. See also CAN.
CAN-LO	CAN Low. One of the two data lines in the CAN bus system. See also CAN.
CARB	California Air Resources Board (US air-pollution authority), proper name
CARIN	Autopilot system, Mercedes
CAS CAS	Computer aided service, proper name Collision Avoidance
CAT	Catalytic converter
CB	Vacuum control of starting mixture
CBC	Cornering brake control
CC	Cruise control. See also ACC
CCM	really ccm or cm³, cubic centimeters, unit of volume
CCW	Counter clockwise, e.g. for indicating direction of rotation of engine
CD CDCR	Compact disc Compact Disc Changer Rear
CDI	Common Rail direct injection (in Mercedes and MCC)
CDL	Central door locking, central locking system limited to doors (Opel)
CDN	Canada
CELIS	Central lighting system (Hella)
CEM	Centralised Electronic Module (Volvo)
CFG	Configuration
CFI CFPP	Cylinder-individual injection system, proper name Cold filter plugging point (for diesels)
CGI	Stratified charge gasoline injection, petrol direct injection with stratified charge through  throttle valve and with compressor charging (Mercedes)
CH	Hydrocarbon (normally HC). In conjunction with exhaust-gas systems, HC is understood  to be the portion of unburned fuel in the exhaust, or Switzerland (Confoederatio Helvetica)
CH4	Methane, main component of natural gas (90%), compressed as fuel for natural-gas-powered  cars. See also CNG
CI	Ivory Coast
CID CID	Camshaft identification (position) sensor Colour Info Display
CIFI CIM	Cylinder-individual fuel injection, usually proper name Column Intergration Module
CIN	Calibration identification number. Part of OBD, consists of 3 letters and at most 12 digits.  Can indicate hardware level, for example.
CKP	Crankshaft positioning sensor
CMH	Mixture preheating
CMP	Camshaft positioning sensor
CNG	Compressed natural gas, fuel for vehicles with gas-powered engines
CNS	Combustion noise sensor, measures combustion noises (knock sensor)
CO	Carbon monoxide. Poisonous gas present in exhaust gas. Produced during  combustion of carbon  with insufficient oxygen, or Colombia
CO2	Carbon dioxide, non-poisonous gas produced during combustion,  also known as greenhouse gas
COMAND	Cockpit management and data systems. System for data exchange and driver information  management.
CPS	Camshaft position/speed sensor / Crankshaft position sensor
CPU	Central processing unit (microprocessor)
CPV	Constant pressure valve
CPX	CPx: high-pressure pump of a Common Rail diesel system, such as CP2 . It is used in commercial  vehicles.
CR	Common Rail. See CRS.
CRC	Cyclic redundancy check. Method for generating a checksum, proper name
CRI	Common Rail injector. Injector of a Common Rail system, comparable to the injection valve of  a conventional injection system.
CRIN	Car radio identification number
CRP	Common Rail pump. Special high-pressure pump for the Common Rail system, or  Car phone (Opel)
CRS	Common Rail system. Special diesel direct-injection system in which the fuel is distributed  to the injectors via a common line (Common Rail) under high pressure.
CRT	Master computer or Continuous catalytic converter regeneration by burn off at 300°C  with after-injection
CRW	Common Rail parameters (also CR-W)
CS	Crankshaft
CSCV	RPM control valve
CTG	CAN tester (Mercedes)
CTS	Cooling temperature sensor, Kühlmittel-Temperatursensor
CTX	Continuously variable transaxle
CV	Check valve, shutoff valve, throttling non-return valve
CVN	Calibration verification number. Part of OBD, contains the checksums for parameter  settings, for example.
CVT	Continuously variable transmission
CW	Drag coefficient, characteristic value for aerodynamics or drag, determines drag together  with frontal area of vehicle or clockwise, e.g. for indicating direction of rotation of engine
CZ	Czech Republic

D	Diesel engine or Decimal number or Drive (position of automatic-transmission selector lever)  or Germany
D3	German exhaust-gas standard, parallel to European standard. Corresponds largely to EU3.  See EU3 and EURO3.
D4	German exhaust-gas standard, parallel to European standard. Corresponds largely to EU4.  See EU4 and EURO4.
DA	Boost pressure dependent full-load stop
DAB	Digital audio broadcasting
DBC	Dynamic brake control
DBE	Roof operating unit, control unit in Mercedes, usually proper name
DBG	Flow limiter
DBR	Retarder (sustained action brake) or Retarder relay
DBV	Pressure limiting valve
DC	Direct current or DaimlerChrysler
DCU	Diesel control unit or Dosing control unit. Unit for injection of urea (serves to reduce NOx).
DD	Fuel pressure limiter
DDA	Digital directional antenna, special antenna which blocks out radio wave reflection interference
DDE	Digital Diesel Electronics, system name, usually proper name, or Direct data exchange
DDM DDM	Engine speed versus alternator residual ripple or driver door module (Opel) Drivers Door Module
DDS	Diesel theft protection
DECT	Digital enhanced cordless telecommunications, standard for data transmission, usually proper name
DEE	Digital engine electronics
DF	RPM sensor, or Pressure sensor, or Direct-fire, distributorless coil ignition with double ignition coil
DFA	Speed sensor output
DFB	Flow limiter (Common Rail) or Dynamic start-of-delivery setting
DFC	Deceleration fuel control
DFHL	Speed sensor, left rear
DFHR	Speed sensor, right rear
DFM	Dynamo field monitor. Output for recording dynamo field
DFS	Double-spark coil, supplies two cylinders
DFVL	Speed sensor, left front
DFVR	Speed sensor, right front
DG	Speed sensor, or Speed sensor for transmission input speed
DGI	Direct gasoline injection
DHK	Nozzle holder combination
DI	Direct (diesel) injection, system name, usually proper name
DI/DIST	Distributor type
DIA	Diagnosis
DIAGK	Diagnosis K line, communication line
DIAGL	Diagnosis L line, signalling line
DIGI	Digiplex (Marelli)
DIGIJET	Digitally controlled fuel injection, system name, proper name
DIGIPLEX	Fully electronic ignition system, system name, proper name
DIGNITION	Electronic ignition system, system name, proper name
DIN	German Industrial Standard
DIO	Data input/output. Interface for exchanging data in both directions.
DIS	Direct ignition system, proper name
DISA	Differential intake manifold system (switchable, variable-length intake manifold)
DK	Throttle valve or Denmark
DKA	Throttle valve actuator, Ecotronic
DKE	Throttle valve incrementation bit
DKG	Throttle valve sensor, detects current position of throttle
DKI	Throttle valve actual value. Current throttle-valve voltage
DKP	Throttle valve potentiometer
DKR	Throttle valve reduction or Throttle valve reduction bit
DKS	Throttle valve switch
DKV	Throttle valve preset
DLB	Compressed-air brake
DLC	Data link connector. Diagnosis connection
DLI	Distributorless ignition
DLK	Dynamic steering correction
DLOC	Device location, Einbaulage einer Komponente
DLS	Digital idle stabilisation
DLWR	Dynamic headlight vertical aim control
DM	dm: decimeter DM: Diagnosis module
DM3/H	dm³/H: cubic decimeters per stroke, unit
DME	Digital Motor Electronics (Motronic), system name, proper name
DMM	Digital multimeter
DMS	Elongation measurement sensor
DMV	Diesel solenoid valve
DOHC	Double overhead camshaft, usually part of engine designation
DP	Dashpot, or Throttle valve closing damper
DPF	Diesel particle filter
DPFE	Delta pressure feedback electronic system or Differential pressure feedback, EGR
DPHI	dphi, delta phi, difference angle. See also PHI.
DQ	dQ: delta quantity, difference quantity. See also Q.
DR	Pressure regulator
DRM	Pressure regulator module
DRS	Rotation rate sensor, sensor for vehicle dynamics control
DRV	Pressure regulator valve
DS	Pressure switch or Pressure sensor
DSA	Dynamic stability assistance
DSB	Pressure sensor in/for combustion chamber
DSC	Dynamic stability control
DSE	Thermal-expansion material element, expands or contracts when heated
DSG DSM	RPM target value sensor Drivers Seat Module
DSP	Display, or Dynamic shift program (automatic transmission), or Digital sound package  (VW audio equipment variant), or Digital sound processor, special processor for digita l processing of audio signals
DSS	Pressure-jump switch
DSTC	Dynamic stability and traction control
DSU	Pressure sensor for ambient pressure
DSV	Pressure control valve
DTC	Diagnostic trouble code
DTI	Diesel direct-injection with distributor pump (Opel)
DTR	Distronic. Distance control system (Mercedes)
DV	Pressure supply, or Throttle device
DVD	Digital versatile disc. Storage medium with significantly higher storage capacity than  a conventional CD.
DVH	Pressure valve holder
DWA	Theft warning system, BMW-specific designation
DWS	Rotation angle sensor
DYN	Dynamic
DZ	Breakthrough ignition or Algeria
DZG	RPM sensor
DZV	Digital ignition, fully electronic
E	Electrical fan, or Fuel-injection engine, or Economy (shifting program for automatic  transmissions), or Spain (España)
EA	Original equipment
EAG	Electronic automatic transmission
EAI	Electronic advanced ignition, electronic ignition-curve control, ELZ
EAK	Kenya
EAS	Electronically autonomous starting system or electronic actuation system,  usually trade name  or electronic air suspension (VAG)
EAV	Element shutoff valve. Shuts off an individual element of the high-pressure pump in the  Common Rail system.
EBC	Electronic brake force control (see EBD and EBV)
EBCV	Electrical auxiliary air control valve
EBD	Electronic braking differential or Electronic brake force distribution (see also EBC and EBV)
EBM	Electronic brake management system. Optimises driving stability, traction, and braking  function (BMW)
EBS	Electronic braking system
EBV	Electronic brake force distribution (see also EBD and EBC)
EC	Ecuador
ECABS	Electronic air cushioning, combined with ABS
ECC	Electronic climate control, electronically controlled air conditioner (Opel)
ECD	Electronically controlled deceleration
ECE	Economic Commission of Europe, proper name
ECI	Electronically Controlled Injection, system name, usually proper name
ECM	Electronic Control Module, system name, usually proper name
ECO	Ecotronic, system name, usually proper name
ECON	ECOn: Electronic carburetor, n=version, usually proper name
ECONZ	ECOnZ: Electronic carburetor and electronic ignition, n=version number, usually proper name
ECT	Engine coolant temperature, or temperature sensor
ECU	Electronic control unit, proper name
EDC	Electronic diesel control, usually proper name
EDG	Electronic diesel control with integrated transmission control. MCC control unit, proper name.
EDIS	Electronic documentation and information system (Bosch)
EDIS 4	EEC IV with distributorless ignition system (Ford)
EDR	Electronic diesel control NFZ-DB
EDS	Electronic differential lock, usually proper name
EDW	Electronic anti-theft warning system or Electronic pressure transducer
EEC	Fully electronic engine control or Electronic ignition timing, proper name
EEC IV	Electronic engine control system IV (Ford), system name, proper name
EECS	Fuel vapour emission control system
EEM	Electrical energy management. Higher-order system that coordinates the interaction  of the generator, battery, voltage converter, drive train, and loads. See also EES and VSC.
EEPROM	Electrically erasable programmable read-only memory, proper name
EES	Electrically unlocked starting quantity, or Electrical energy systems (onboard network  of the future (42V generator for electromagnetic valves, for example, 14V DCDC converter for rest of network)
EFI	Electronic fuel injection, usually proper name
EFP	Electronic accelerator pedal, proper name
EFS	Single-spark coil, supplying one cylinder
EGAS	Electronic accelerator pedal, proper name (electronic throttle control, ETC)
EGD	Electronically regulated shock absorption
EGE	Electronic air dryer unit
EGN	EGn: EGAS control unit, n=version, usually proper name
EGO	Exhaust Gas Oxygen Sensor, unbeheizte Lambdasonde
EGR	Exhaust gas recirculation
EGS	Electronic transmission control
EHA	Electronic automatic heater, usually proper name
EHAB	Electrohydraulic shutoff
EHB	Electrohydraulic brake
EHCM	Electrohydraulic control module
EHPS	Electrohydraulic power steering
EHR	Electrohydraulic lifting control
EHS EHU	Electrohydraulic control module Entertainment Head Unit
EHSW	Electrohydraulic positioner
EI	Electronic ignition
EKE	Electronic fuel injection, proper name
EKM	Electronic clutch management
EKP	Electric fuel pump
EKRG	Simple short-circuit ring sensor
EKS	Electronic clutch system. Clutch engagement and disengagement is automatic.  The clutch pedal is no longer needed. See also AKS.
ELAB	Electrical idle shutoff valve
ELB	Electronically controlled brake
ELD	Electrical load-peak damping
ELF	Electronic air cushioning
ELFI	Electronic vehicle identification. Component of VW ELSA service information system.
ELR	Electrical ignition system with ignition curve adjustment or Electronic idle control
ELRA	Electronic automatic restraint. Automatic seat belts (VW)
ELS	Electronic idle stabilisation
ELSA	Electronic service information system. VW system for authorised workshops (garages).  Comprises the components ELFI, ELWIS, and ETKA.
ELV	Electrical air valve, or Electronic steering or steering-column lock. See also ESL.
EL-V	Electronically controlled carburetor
ELWIS	Electronic shop information system. Component of the VW ELSA service information system.
ELZ	Electronic ignition
EMAB	Shutoff by electromotor
EMB	Electromechanical brake
EMC	Electromagnetic compatibility (see also EMV)
EMF	Electromechanical parking brake.
EMI	Injection volume indicator
EML	Electronic engine performance control, proper name
EMR	Electronic volume reduction
EMS	Electronic engine control, proper name
EMSE	Electromagnetic start enable
EMV	Electromagnetic compatibility (EMC)
ENG	Engine type (code letters), or Engine
ENG FAIL	Engine failures, diagnosis line for outputting errors
ENR	Electronic level control
EOBD	European on-board diagnosis, internal vehicle diagnosis with external tester conforming  to European guidelines. Serves primarily to record exhaust-gas related faults. Usually  trade name
EOL	End of line, usually in conjunction with end-of-line programming
EP	Adjustment point
EPA	Environmental Protection Agency, air purity monitoring organisation
EPAS	Electric power-assisted steering
EPB EPB	Electropneumatic brake Electronic Park Brake
EPC	Electronic power control or Electronic pedal control (such as with ME-Motronic systems  without mechanical throttle cable)
EPI	Exhaust Port Injection, Nacheinspritzung in Auslasskanal (Toyota)
EPK	Electropneumatic kit
EPROM	Erasable programmable read-only memory, programmable or erasable with UV light, proper name
EPS	Extended park position, or Injection pump test bench, sometimes used as a product  identification (such as EPS 944)
EPSV	Electrical injection adjustment
EPT	Electronic pressure transmission
EPW	Electro-pneumatic transducer, serves to transform electrical signals into pneumatic  signals such as in boost-pressure regulation
ER	Energy reserve
ERE	Electronic inline injection system (special engine control) or Electrical regulator
ERW	Energy reserve with voltage converter
ERWIN	Electronic repair and workshop information. VW electronic service information system  for independent workshops (garages) and fleet operators. Information offering is  restricted compared to ELSA.
ES	Electronic control unit or El Salvador
ESA	Emissions system analysis, product name for exhaust-gas tester (Bosch) or  Electronic spark advance
ESA/IZA	Map ignition, ignition coil in distributor
ESC	Escape key on PC or Map ignition or Electronic spark control, electronic ignition contro l up to knock region, with knock sensor
ESG	Single-pane safety glass or Electronic switching unit for trailer detection  (used in brake systems)
ESGN	ESGn: Special equipment, e.g., NWS, ETS, KGE, n=version no.
ESL	Electronic steering lock. See also ELV.
ESP	Electronic stability program, another designation for vehicle-dynamics control (FDR),  usually proper name
ESPV	Electrical injection adjustment
ESR	Electronic slip reduction, another name for ASR, or Electrical sunroof, electrically operated sunroof (or lifting roof)
ESS	Electronic suspension systems. Continental Teves electronic air cushioning system.  The system adapts automatically to vehicle load conditions, has continuously variable  damping, and works together with ESP.
ESSD	Electrical steel sunroof
EST	Electronic spark timing, electronic map ignition control. See also MSTS
ESV	Feed valve or Injection valve
ET	Egypt
ETC	Electronic throttle control, usually proper name or Electronic traction control
ETKA	Electronic parts catalogue. Component of the VW ELSA service information system.
ETM	Electronic transmission management, usually proper name
ETS	Electronic thermostat control, usually proper name or Electronic traction system, see ETC
ETV	Electronic throttle valve
EU	European Union
EU3	European exhaust-gas standard, valid from 2000 (levels: HC 0.2, CO 2.3, NOx 0.15)
EU4	European exhaust-gas standard, valid from 2005 (levels: HC 0.1, CO 1.0, NOx 0.08)
EUI	Electronic unit injector, injection nozzle of pump-nozzle system (diesel injection)
EUP	Electronic unit pump, diesel pump of pump line nozzle system (diesel injection)
EURO3	European exhaust-gas standard, valid from 2000 (levels: HC 0.2, CO 2.3, NOx 0.15)
EURO4	European exhaust-gas standard, valid from 2005 (levels: HC 0.1, CO 1.0, NOx 0.08)
EUV	Electro-reversing valve
EV	Injection valve or Inlet valve of pressure control valve or Inlet valve of ABS system
EV1	Injection valve for high pressure
EV2	Injection valve for low pressure
EVA	Electrical full-load stop or Emergency valve assistance, safety valve
EVAP	Fuel vapor emission control
EVE	Electronic distributor injection system (special engine control)
EVR	Electronic vacuum regulator
EWD	Single-coil actuator, servomotor with one winding
EWL	External warning lamp
EWM	Electronic selector-lever module. Control unit in Mercedes, usually proper name
EWMA	Exponential weighted moving average, misfire detection during last 10 driving cycles
EWS	Electronic immobilizer
EX	Exhaust (or outlet, exhaust-gas recirc. valve, exhaust manifold)
EZ	Electronic ignition, usually proper name
EZE	Electronic central control unit, usually proper name
EZF	Electronic ignition system, map-controlled
EZF-H	Electronic ignition system with map, trigger by Hall sensor
EZF-I	Electronic ignition system with map, trigger by inductive sensor
EZK	Electronic ignition with knock control
EZ-K	Electronic ignition timing with knock controls, proper name
EZL	Electronic ignition system with characteristic curves
EZL-H	Electronic ignition with characteristic curves, trigger by Hall sensor
EZS	Electronic ignition switch
EZV	Electronic ignition timing
F	France
F/P	Fuel pump
FA	Front axle
FAB	Failcode Airbag. Output line for error codes for airbag system (Mazda)
FAC	Failcode Air Conditioning. Output line for error codes for air conditioner (Mazda)
FAP	Accelerator pedal or Vehicle analysis protocol. Log maintained by tester during diagnosis.  Can be printed and given to vehicle owner as evidence of repairs performed..
FAS	Driver-assistance system
FAT	Failcode Automatic Transmission. Output line for error codes for transmission control (Mazda)
FB	Fast burn, rapid spread of flame front or Start-of-delivery, key parameter in diesel injection  systems or Remote control
FBA	Parking-brake system (usually hand brake)
FBB	Start-of-delivery blocking
FBG	Start-of-delivery sensor
FBKW	Crankshaft angle at start-of-delivery
FBN	Start of delivery, normal
FBR	Start-of-delivery control
FBS	Driving enabling system (Mercedes), or Failcode Brake System. Output line  for error codes for  ABS system (Mazda)
FBV	Parking brake valve
FC	Fault (error) code
FCKW	Chlorofluorocarbon (CFC). Gaseous chemical compound that destroys the ozone layer.  Contained in old refrigerants (R12) for air conditioners.
FCV	Fuel cell vehicle. Vehicle with fuel-cell drive, up to now only a Ford prototype.
FD	Date of manufacture
FDI	Fuel direct injection, gasoline direct injection, refer also to GDI
FDR	Trip computer or Vehicle dynamics control
FDS	Ford diagnostic system
FE FEC	Delivery units, parameter for determining delivered fuel amount Front Electrical Centre
FEN	Failcode Engine. Output line for error codes for engine control unit (Mazda)
FES	Spark energy control
FFG	Accelerator pedal
FFR	Vehicle master computer. Diagnostic gateway in vehicle, installed in combined instruments  or central electrical system. Also contains the immobilizer.
FGB/AGB	Speed limiter / automatic speed limiter, usually proper name
FGB/GBA	Speed limiter / speed limiting system, usually proper name
FGG	Speed sensor
FGR	Speed control, usually proper name
FH	Power window
FHE	Road and obstacle detection
FHM	Power window motor
FI	Filter
FICD	Fast-idle control device
FIN	Finland
FIS	Vehicle information system. Product designation (such as FIS 215)
FJI	Fiji Islands
FKT	Function
FKTSCH	Function switch
FLA	Vehicle performance analysis, product name for performance test stand (Bosch) , or Spring-loaded idle stop
FM	Vehicle management
FMN	Delivery volume normal
FMVSS	Federal motor vehicle safety standard
FN	Vehicle level
FP	Accelerator pedal or Delivery pump
FPK	Freely programmable combined instruments
FPM	Accelerator pedal module
FPR	Fuel pump relay
FR	FR signal: provides engine or engine/transmission control unit with information about generator load.
FRS	Freewheel pulley
FS	Driving-mode switch or Driver side
FSA	Vehicle system analysis, product name for engine tester (Bosch)
FSD	Folding sunroof
FSG	Chassis control unit or Fill-level sensor
FSK	Frequency shift keying
FSR	Driving stability control
FSS	Delivery signal sensor, or Flexible service system
FTCO	Flat tachograph (new, flat design), Mercedes
FV	Filling valve
FWA	Chassis analysis. Sometimes also used as product designation (such as FWA 400)
FWI	Vehicle-travel pulse number
FZ	Vehicle
FZG	Vehicle
FZK	Vane compressor
FZR	Vehicle controller, ESP system component
G	g: Acceleration of gravity, or gram, physical unit G: G-signal : crankshaft signal for TDC,  4 signals for the control unit per distributor rotation
G/SEC	g/sec: grams per second, unit
G/ZYL	g/Zyl: grams per cylinder, unit for mass per cylinder
GA	Basic adaptation or Guarantee
GATES	Global automotive telematic standard
GB	Yawing moment restriction or Great Britain
GBA	Seat belt positioner drive
GBR	Seat belt positioner
GDB	Regulated differential brake
GDI	Gasoline direct injection, designation for petrol direct injection systems or vehicle models  with this system. Usually proper name.
GDL	Gas pressure lamp (Audi)
GDV	Constant pressure valve
GEN	Generator
GER	Germany
GGF	ggf.: possibly, if necessary
GGS	Transmission group switch
GHD	Housing cover
GID	Graphic information display (Opel)
GK	Glow plug
GM	Basic module, or Gear motor, or General Motors, proper name (name of vehicle manufacturer)
GMA	Yawing moment buildup delay
GMR	Mixture regulator
GND	Ground
GOL	Persian Gulf states
GPS	Global Positioning System, satellite system for locating a vehicle
GR	gr: large Gr: Group GR: Gas retention, or Greece
GRA	Speed control system. Alternative term for cruise control.
GRV	Constant-volume valve
GS	Independent electronic transmission control, usually proper name, or Belt tensioner
GS 1.2	Electronic transmission control, Version 1.2, system name, proper name
GSG	Speed sensor
GSH	Gas sensor hydrocarbon, hydrocarbon sensor
GSK	Sheathed element glow plug
GSM	Global system for mobile communication
GSR	Belt tensioner, usually proper name
GSS	Transmission shift lock or Seatbelt buckle switch
GST	Stepped start volume
GSY	Speed symbol. Specification on tyres for allowable speed, alphabetic. See also Speed Index
GUS	Belt tensioner or Commonwealth of Independent States (CIS)
GW	Gateway. PC or computer that connects and controls data exchange between two networks.
GWK	Transmission converter clutch
GZS	Glow duration control unit

H	h: hours H: hexadecimal number, or stroke, or Hungary
HA	Hydraulic stop or Rear axle or Hydraulic modulator for ABS
HAC	Height compensation
HAI	Hot-air inlet
HAS	Hand brake switch
HAU	Automatic heating
HBA	Hydraulic brake assistant or Hydraulically operated equalisation or Auxiliary brake system
HBZ	Master brake cylinder
HC	High compression or Version with high compression ratio or Hydrocarbon
HD	Heating wire or Lifting roof
HDC	Hill descent control. Special system that maintains speed downhill. Works using brake  intervention at about 5 mph (8 km/h) (BMW and Rover offroad vehicles)
HDEV	High-pressure injection valve
HDF	Remote boot-lid release
HDI	High-pressure direct injection
HDK	Half-differential short-circuit ring travel sensor
HDP	High-pressure pump
HDS	Urea metering system, used with diesel vehicles to prevent or reduce soot emissions
HE	Main injection
HEGO	Heated exhaust-gas oxygen sensor
HEI	High performance ignition system, transistorized ignition, contactless ignition
HEV	High-pressure injection valve
HF	High frequency
HFG	Hand-operated gas delivery, for example in special vehicles for handicapped drivers
HFM	Hot-film air-mass sensor or Special engine control in which load detection takes place  via a hot-film air-mass sensor
HH	HH division, 4/4 division of brake circuit: circuits 1 and 2 brake all wheels.
HHC	Hill Holder Control, ESP system component
HHT	Hand-held tester (such as KTS500 or PMS100)
HIC	Hot idle compensation
HID	Hill descent (sensor). Sensor that registers downgrades or vehicle rolling. See HDC.
HK	Height correction or Hong Kong
HKD	High-voltage trigger diode, special diode installed in ignition coils
HKZ	High-voltage capacitor ignition
HL	Left rear
HLM	Hot-wire air-mass sensor
HO2S	Heated oxygen (O2) sensor
HP	Hydraulic pump
HPA	hPa: hectopascal, physical unit
HPDI	High pressure direct injection
HPI	High-pressure injection. Direct-injection petrol engine used in Citroen and Peugeot.  Comparable with GDI.
HR	Hybrid control, or Right rear, or Croatia
HRA	Rear window washing system
HSCAN	High-speed controller area network. CAN bus with high transmission rate (Opel).  See also CAN, LSCAN, and MSCAN.
HSPV	Hydraulic injection timing device
HSV	High-voltage distribution or Hydraulic start lock
HT	HT division. 4/2 division of brake circuits: circuit 1 brakes all wheels, circuit 2 the front wheels
HU	Major inspection
HW	Hardware
HYAB	Hydraulic shutoff device
HZ	HZ: Master brake cylinder Hz: hertz, physical unit
HZR	Heating control. Simple type of air conditioner.
I	Italy
I1	Incremental system with one sensor
I2	Incremental system with two sensors
IAC	Idle air control, i.e. idle speed control, for injection engines
IAM	Independent after-market. Service or spare-parts dealers independent of vehicle  manufacturer.
IC	Integrated circuit
ICC	Intelligent cruise control, Nissan distance control system; see also ACC.
ICE	Ignition control electronics, electronic ignition system
ICM ICM	Ignition control module, or Integrated chassis management, BMW vehicle-dynamics  control with trend-setting technology Infotainment Module
ID	Identifier, bei CAN-Bus-Systemen eine Art Address-Byte, das angibt, für wen ein Datenblock bestimmt ist oder Identifikation
IDI	Indirect (diesel) injection
IDIS	Integrated driver information system, similar to navigation system
IDS	Interactive dynamic driving system
IFS	Inertia fuel shutoff. Safety fuel shutoff, or Independent front-wheel suspension
IFZ	Infrared central locking
IG	Pulse or increment transmitter, or Ignition
IHE	Integrated hydroelectronics unit. Control electronics, hydraulic generator, and electric  motor in Citroen Hydraktiv chassis.
IHKA	Integrated heating and air conditioning system (BMW)
IHR	Heating control, usually proper name
IIA	Integrated ignition system
IL	Israel
ILV	Integrated quiet-running system
IMA	Integrated engine assistant (special Honda engine control), or Injector quantity analysis
IMM	Immobilizer
IMMO	Immobilizer
IMP	Pulse(s)
IN	Inlet (intake) manifold or valve
INA	Information display for ASR systems
IND	India
INFOANZ	Information display for ASR systems
INJ	Injector. Injection jet or valve in Common Rail diesel system
INT	Integrator
INZ IPBEC	Central injection Instrument Panel Body Electrical Centre
IPS	Intelligent Protection System, integrated two-stage airbag system with retractable  pedals, head/shoulder airbags, and active headrests. Used in Ford Mondeo.
IR	Individual control with commercial-vehicle ABS systems, or Infrared, or Iran
IRF	Interior filter
IRM	Individual control, modified, with commercial-vehicle ABS systems
IRQ	Iraq
IRS	Interior protection
IS	Iceland
ISA	Idle speed correction or Intelligent speed adaptation: Use of a GPS system and traffic-sign  database to automatically regulate speed (system still in test phase)
ISC	Idle speed control or Idle compensation
ISDN	Integrated Services Digital Network: digital telephone and data network  with integrated services
ISF	Vehicle information system
ISIS	Intelligent safety system. System with multiple airbags, pyrotechnically  triggered headrests, seat-belt tensioners and intelligent electronics (BMW)
ISO	International Organisation for Standardisation
ISO-EGO	Isolated Exhaust Gas Oxygen Sensor, isolierte unbeheizte Lambdasonde (mit Massekabel)
ISO-HEGO	Isolated Heated Exhaust Gas Oxygen Sensor, isolierte beheizte Lambdasonde (mit Massekabel)
ISS	Joint venture (Bosch, Michelin) for developing integrated vehicle dynamics systems
ISU	Intelligent switching unit (Siemens)
ITGS IVLAN	Intelligent traffic guidance system (Mercedes) In Vehicle Local Area Network
IWG	Inductive travel sensor
IWZ	Incremental angle/time sensor, rotation-angle sensor
IZA	Integrated ignition system
IZV	Infrared central locking
J	Japan
JA	Jamaica
JET	Jet, Jetronic: injection system, usually proper name
JOBD	Japanese OBD, OBD standard for Japan
JTS	Jet thrust stoichiometric. Direct-injection petrol engine (Alfa)
JW	Company car(s)
K	k: small K: channel K-line: bidirectional line between control unit and tester
KA	Knee airbag
KAM	Keep-alive memory
KAT	Catalytic converter
KB	Wire harness
KBA	Federal Motor Vehicle Office (Germany)
KBZ	Combination brake cylinder
K-CAN	Body CAN bus. Low-speed CAN bus for comfort-system and body electronics. See also PT-CAN and SI-BUS.
KD	Kickdown or Customer service
KDS	Kickdown switch
KE	Continuous injection, usually proper name
KE-MOTRONIC	Continuous electronic injection system, usually proper name
KEN	KEn: Jetronic, continuous, with electronic extended-function unit, n=version, usually proper name
KF	Fuel filter
KFB	Fuel filter, petrol or Comfort zone
KFMG	Continuous delivery-volume meter
KFZ	Motor vehicle
KG	kg: kilogram, physical unit, or Keyless Go (access to vehicle and engine start without key)
KG/H	kg/h: kilograms per hour, unit
KGE	Crankcase ventilation
KIW	Combined instruments with service-interval indicator. See also SIA.
K-JETRONIC	Continuous injection system, usually proper name
KL	KL or Kl: Terminal
KLA	Automatic climate control
KM	km: kilometer, physical unit KM: small engine
KMA	Continuous volume analysis, product name (Bosch)
KMM	Continuous volume meter, checks fuel delivery
KMMG	Continuous volume meter, closed
KMV	Refrigerant compressor
KOM	Commercial bus and rental vehicles
KOMP	Component
KPA	kPa: kilopascal, physical unit
KPN	Kpn: Motronic (load detection occurs via intake manifold pressure, n=Motronic version, usually proper name)
KR	Anti-knock control
KRF	Kraftstoffrückführventil (Diesel)
KRS	Anti-knock control interface or Fuel return valve
K-RWG	Short-circuit ring sensor
KS	Fuel reservoir, or Knock sensor
KSA	Kingdom of Saudi Arabia
KSB	Cold-start accelerator, with distributor injection pumps
KSE	Child-seat detector
KSH	Cold-start aid
KSP	Fuel reservoir
KSS	Cold-start control
KSV	Cold-start valve
KSZ	Fuel distributor or distribution
KTF	Fuel temperature sensor, or Coolant temperature sensor
KU	Clutch
KU/GN	Clutch/transmission neutral position
KUKO	Coupling head
KVA	Fuel consumption gauge
KVD	Fuel evaporation
KVR	Fuel distributor tube
KVRS	Evaporative emission-control regeneration system, also referred to as tank  ventilation system
KVRV	Fuel evaporation regeneration valve, tank ventilation valve
KVS	Fuel distributor piece
KW	kW: kilowatt, physical unit KW: crankshaft or crankshaft angle or shortwave (radio)
KWH	kWh: kilowatt-hours, physical unit
KWP 2000	Keyword Protocol 2000, log for transmitting diagnostic data
KWS	Comfort immobilizer
KWT	Kuwait
KX	Kx: Jetronic, continuous, with oxygen sensor control, usually proper name
KZS	Capacitor intermediate storage

L	l: liter, physical unit, or left L: left L-line: unidirectional line between control unit and tester
L/H	l/h: Liters per hour, unit
L/KM	l/km: liters per kilometer, unit
LAM	Idle emissions measurement
LAV	Luxury activity vehicles (vehicle classification, such as Lexus RX 300)
LC	Low compression, or Version with low compression ratio
LCD	Liquid crystal display, usually proper name
LDA	Boost-pressure-dependent full-load stop, with distributor injection pumps
LDF	Boost-pressure sensor
LDR	Boost-pressure control, or Idle speed control
LE2-JET	Petrol injection, LE-Jetronic, 2nd generation, usually proper name
LED	Light-emitting diode, usually proper name
LEN	LEn: Jetronic, intermittent, covers European functionality, n=version, usually proper name
LER	Idle limit-speed control
LEV	Low-emissions vehicle. Designation for vehicles with low emissions level.  See also NLEV, SULEV, TLEV, ULEV, and ZEV.
LFB	Load-dependent start-of-delivery, with distributor injection pumps
LFR	Idle compensation
LFT	Air temperature sensor, or Long (term) fuel trim (to counteract aging symptoms). See also LTFT.
LHA	Air-side automatic heater
LHD	Left-hand drive
LH-JETRONIC	Same as L-Jetronic with hot-wire air-mass sensor, usually proper name
LHN	LHn: Jetronic with hot-wire air-mass sensor, intermittent, n=version, usually proper name
LI	(also li:) Left, or Load index, number indicating tyre load capacity
LIA	Lift axle
LIM	Sedan
L-JETRONIC	Electronically controlled injection system (with direct air-mass measurement),  usually proper name
LKE	Load piston unit
LL	Idle, engine operating state or Left-hand drive or LL division, triangular division of brake circuits: 2 circuits in front, one in rear
LLDRAN	Idle speed increase
LLK	Charge-air cooling
LLR	Idle control (diesel systems)
LLRA	LLRa: Idle control with adaptive pilot control
LLS	Idle actuator, or Idle switch
LL-STAB	Idle stabilization
LM	Air-flow sensor (also LMM)
LMF	Light-alloy rims
LMM	Air-mass sensor, or Air-flow sensor
LMS	Air-mass sensor
LN	Ln: Jetronic with air-flow sensor, intermittent, n=version, usually proper name
LOS	Emergency program (EEC IV)
LP	Perforated plate
LPG	Liquefied petroleum gas, fuel for vehicles with gas-powered engines
LPS	Circuit board circuit
LPT	Printer port or interface on PC
LR	Oxygen sensor control
LRA	LRa: oxygen sensor control with adaptive pilot control
LRD	Load response drive, alternative multifunction control
LRR	Smooth-running control, or Long-range radar (component of ACC system with  detection range up to 120 m)
LRS	Load response start, alternative multifunction control
LS	Release switch or Oxygen sensor
LSCAN	Low-speed controller area network. CAN bus with low transmission rate (Opel). See also CAN, MSCAN, and HSCAN.
LSD	Limited-slip differential
LSF	Oxygen sensor, planar (flat sensor)
LSH	Oxygen sensor, heated
LSM	Oxygen sensor for lean operation
LSP	Longitudinal lock shutoff
LSU	Wideband oxygen sensor, planar type
LSZ	Light-switching centre
LT	Model designation for VW Transporter, proper name
LTCC	Low temperature cofired ceramic, multilayer ceramic technology
LTF	Air-temperature sensor
LTFT	Long-term fuel trim (to counteract aging symptoms). See also LFT.
LTG	Line
LTR	Liter, physical unit, often also ltr, L
LUN	LUn: Jetronic, intermittent, with USA functionality, n=version, usually proper name
LWL	Optical fiber
LWR	Headlight vertical aim control
LWS	Steering wheel angle sensor. Component of ESP system, determines steering-wheel rotation
M	M: Motronic, usually proper name, or Mechanical or Mechanical fan or Centre m: Centre or Manual
M/S2	m/s²: meters per second per second, physical unit for acceleration
M3/H	m³/h: cubic meters per hour, unit
MA	mA: milliampere, physical unit MA: Mono-Motronic, petrol injection system, usually proper name
MAEL	MaEl: earth (ground) electrode (spark plug)
MAF	Mass airflow sensor
MAL	Malaysia
MAP	Manifold absolute pressure or Intake manifold pressure sensor
MAR	Quantity compensation control
MAS	Control unit for engine assembly
MAT	Manifold absolute temperature
MAX	Maximum
MBAR	mbar: millibar, physical unit
MBS	Engine-brake switch
MBZ	Diaphragm brake cylinder
MC	Microcomputer or Medium compression
MCC	Micro Compact Car. DaimlerChrysler subsidiary that manufactures the Smart vehicle.
MDA	Engine speed increase
MDF	Mass of wheel-speed sensor, usually with an indication of the particular sensor (left front,  right front, etc.)
MDR	Membrane pressure control
ME	Motronic with electronic gas pedal, usually proper name, or Control unit for volume  regulation in diesel systems, usually proper name
MEA	Middle East
MEAB	Mechanical shutoff device (diesel EDC). In newer systems, the shutoff is electrical (see ELAB).
MECH.	Mechanical
MED	Motronic with ETC and petrol direct injection
MEG	Motronic with ETC and transmission control
MEINS	Meins: Injection volume (in mg/stroke or mg/s)
MEN	Monitor engine (output line for engine diagnostic data)
MEP	Mean effective pressure
MES	Mechanically enabled start volume
MEX	Mexico
MF	Measurement window
MFA	Measurement window, start or Multifunction display
MFD	Multifunction display
MFE	Measurement window, end
MFI	Multipoint fuel injection (electronic)
MFI-C	Continuous multipoint fuel injection (electronic)
MFI-I	Intermittent multipoint fuel injection (electronic)
MFI-S	Sequential multipoint fuel injection (electronic)
MFL	Multifunction steering wheel
MFR	Multifunction control
MFS	Multifunction sensor
MFU	Multifunction clock
MG	Manual transmission
MG/H	mg/H: milligrams per stroke, unit
MG/ZYK	mg/Zykl: milligrams per cycle, unit
MGND	Engine ground (earth)
MHDI	Mechanical high-voltage distribution ignition
M-HEAT	Mirror Heating, Spiegelheizung (Opel)
MI	mi: Miles, physical unit MI: Malfunction indicator or Main injection (see also HE)
MIC	Microplex (Marelli)
MICROPLEX	Fully electronic ignition system with knock control
MID	Multifunction information display
MIEL	MiEI: Middle electrode (spark plug)
MIL	Malfunction indicator lamp
MIN MIU	Minimum Main Instrument Unit
MJ	Mono-Jetronic, usually proper name or Model year
M-JET	Mono-Jetronic, usually proper name
MK	Motronic with continuous fuel metering, usually proper name
MKV	Multiplicative map adjustment, or Fuel ratio mixture
ML	Motronic with flap air-volume sensor, usually proper name
MLA	Multiple link antitheft system (system-wide theft protection)
MLD	Mechanical load-peak damping
MLN	MLn: Motronic based on air-flow sensor, n=version, usually proper name. See also LM.
MM	mm: millimeter, physical unit
MM3/H	mm³/H: cubic millimeters per stroke, unit
MMI	Engine torque, actual value or Man-machine interface (Porsche designation)
MMM	Multipath map matching (navigation system)
MMS	Engine torque, nominal value
MMV	Quantity solenoid valve
MN	Mn: Motronic, universal load detection (HLM, LM), n=version, usually proper name
MNEFZ	Modified new European driving cycle (exhaust-gas test cycle). See also NEFZ.
MODIC	Mobile diagnosis computer (BMW diagnostic tester)
MOLIS	Modular lights system. LEDs in modular system for rear lights, for example (BMW)
MOST	Media oriented system transport. Usually in conjunction with a bus system (MOST bus),  via which various control units in the vehicle communicate with each other.
MOT	Engine tester, product name (Bosch) or Engine test
MOT/DME	Digital Motor Electronics (Motronic)
MOZ	Engine octane number. Expresses the knock resistance of petrol fuel (US variant of ROZ).
MP	Motronic with intake manifold sensor, usually proper name
MPA	MPa: megapascal, physical unit
MPFI	Multi-point fuel injection, electronic, usually proper name
MPH	mph: Miles per hour, physical unit
MPI	Multi-point injection, fully electronic engine control, usually proper name
MPN	MPn: Motronic in which load detection is via intake manifold pressure, n=version, usually  proper name
MPV	Multi-purpose vehicles (Mazda). Comprises the group of vans and small panel trucks.
MR	Engine relay or Engine control for ASR
MR-DF	Speed sensor with magnetoresistive measurement
MRS	Multi-restraint system. Temic or BMW system consisting of belt tensioner,  belt force limiting,  airbags, and safety battery terminal (see SBK).
MS	ms: millisecond, physical unit MS: Engine control or Diesel systems with electronic volume-  and start-of-injection control
MSA	Designation for diesel injection systems having an electronic volume control,  start-of-injection control, and exhaust-gas recirculation. Systems without exhaust-gas recirculation are  designated  simply as MS.
MSCAN	Medium-speed controller area network. CAN bus with medium transmission rate (Opel).  See also  CAN, LSCAN, and HSCAN.
MSG	Engine control unit
MSR	Engine drag torque control, usually proper name
MST	Measurement and control unit
MSTS	Microprocessor spark timing system, electronic ignition with map control (ELZ),  or Multi spark  timing system, function as for EST. MSTS, however, is not an integrated  part but rather a  separate ignition control unit
MT	Manual transmission or Mechanical transmission or Volume divider
MTCO	Tachograph
MTM	Engine measurement technology module
MUD	mUD: With vacuum
MUX	Multiplexer or multiplex signal
MUXPORT	Multiplexer-Port, Schnittstelle am PC, an die der Multiplexer angeschlossen ist oder  angeschlossen werden kann
MV	mV: millivolt, physical unit MV: Solenoid valve
MVEG	Motor vehicle emission group, exhaust-gas classification for passenger cars
MVL	Lift axle valve with electronic air-cushioning system
MVLDR	Solenoid valve for boost pressure control
MVN	Level valve with electronic air-cushioning system
MVS	Solenoid valve control unit
MW	AM (radio), or Measurement
MY	Model year
MZ	Magneto ignition
MZV	Microprocessor-controlled ignition adjustment
N	n: RPM, or normal N: Selector-lever position (Neutral) for automatic transmissions,  or Norway
NA	Auxiliary drive or Netherlands Antilles
NAS	Auxiliary drive switch
NAV	Navigation or Navigation system
NB	Commercial-vehicle brake
NBE	Proximity detector
NBF	Needle lift sensor (diesel)
NBS	Needle lift sensor (diesel)
NCAP	New Car Assessment Program, better known as EURO-NCAP, association for conducting  more demanding crash tests (with participation of vehicle manufacturers)
NDS	Neutral drive switch, activated when automatic transmission selector  lever is in neutral position
NE	NE: After-injection Ne-Signal: Engine RPM signal, 24 AC signals sent to  control unit per distributor rotation
NEDC	New European driving cycle (procedure for fuel consumption measurement). See also NEFZ
NEFZ	New European driving cycle (procedure for fuel consumption measurement). See also NEDC
NF	Low frequency, or audio frequency
NFZ	Commercial vehicle (lorry, truck)
NHG	Needle-displacement sensor (diesel systems)
NHU	Navigation head unit. Opel navigation control unit.
NIC	Nicaragua
NKW	Lorry (truck)
NKW-ABS	Anti-blocking system for lorries (trucks) with air brakes
NL	Netherlands
NLEV	National low-emission vehicles. US approval level for vehicles that must fulfil the current requirements. See also LEV, SULEV, TLEV, ULEV, and ZEV.
NLK	Follow-on piston
NLS	Needle lift sensor (diesel)
NM	Nm: Newton-meter, physical unit
NM/S	Nm/s: newton-meters per second, unit
NMOT	Nmot: Engine RPM
NOE	Nitrogen oxide emission
NOX	NOx: Nitrogen oxides
NPB	Delivery volume normal test stand (special tester for injection pumps)
NR	Number, or Level control, or Natural rubber (often processed for use in truck tyres).
NRZ	NRZ format: Non-return-to-zero, transmission or pulse form for square-wave  pulses and signals
NS	Fog light(s)
NSW	Fog lights
NTC	Negative temperature coefficient, thermal resistor with negative temperature coefficient, so-called hot conductor
NTC II	Idle speed increase
NTC1	Intake air temperature (in °C)
NTC2	Engine water temperature (in °C)
NVF	Navigation and traffic control
NW	Camshaft
NWS	Camshaft timing
NZ	New Zealand
O2	Oxygen
OAI	Octane adjust input
OBD	On-board diagnostics or off-board diagnostics, vehicle-internal diagnosis with internal or external test unit, usually proper name
OBF	Upper control panel. Above or on the dashboard, some vehicles have switches  or buttons, such as for the rear-window defogger. These elements together  comprise a control panel, which is referred to as the upper control panel to distinguish it from another control panel near the gearshift lever or below the radio.
OBM	On-board measurement
OC	Oxidation catalytic converter
ODFT	Sensor for oil pressure and temperature
ODS	Automatic overdrive control
OEDS	Oil pressure switch
OEF	Location of missing vehicles (via GPS)
OEM	Original equipment manufacturer
OES	Original equipment service. Service or spare parts via the vehicle manufacturer.
OFFSET-V	Voltage offset
OG	Upper limit or Upper tolerance limit
OHC	Overhead camshaft. Camshaft situated above the cylinder head. Often used in  engine designations.
OHV	Overhead valves (the camshaft is therefore underneath)
OMM	Surface micromechanics
OOP	Out-of-position detection
OP	Oil pump
OPC	Opel Performance Centre. Centre for automotive sports (Opel).
OR	Logical OR operation
OSRVM	Outside rear-view mirror (Opel)
OT	Top dead centre
OTA	Oxygen/titanium emissions sensor. Titanium oxide sensor. See also OZA.
OTF	Oil temperature sensor
OUD	OUD: Without vacuum
OUT	Designation on diesel pump for excess-flow restriction screw
OZ	Octane rating. See also ROZ.
OZA	Oxygen/zirconium emissions sensor. Zirconium oxide sensor. See also OTA.

P	Pressure, or Power train (used with OBD error codes, for example), or Portugal
PA	Pa: pascal, physical unit of pressure. See also HPA, KPA, and MPA. PA: Parking assistant
PAG	Polyethylene glycol oil, low-temperature oil
PAM	Parking assistant module (Opel)
PANS	Pans: Intake air pressure (in hPa)
PAS	Peripheral airbag sensor (side airbag)
PASE	Passive start and entry. Keyless access to car and engine start (Siemens system).  Also called Keyless Go (Mercedes, for example)
PATA	Passive button. Button in vehicle with which a function can be set to the passive (off) state
PATS	Passive antitheft system
PB	Pb: chemical symbol for lead (Latin: plumbum)
PBM	Pulse width modulated, signal processing method (prior to sending), usually proper name
PBSL	Park brake shift lock. Selector lever lock for automatic transmission (Opel)
PC	Power control or Personal computer
PCM	Power train control module or Porsche Communication Management, central multimedia control unit for various functions
PCU	Pump control unit (diesel systems), or Power control unit, hybrid-drive control (Honda)
PCV	Positive crankcase ventilation, closed crankshaft ventilation
PD	Pump-nozzle
PDAS	Dynamic 4-wheel control, usually proper name
PDC	Park distance control. Parking aid, often proper name, or Pre-drive check (testing of EHB systems)
PDE	Pump-nozzle unit (new designation is UIS)
PDM	Passenger door module (Opel)
PDOE	Nozzle opening pressure
PEHKS	Pedestrian protection hood kinematics system. Ford mechanical system that raises the hood  (bonnet) in the case of an impact (such as hitting a pedestrian). See also POBSY.
PES	Polyellipsoid system (headlight technique)
PES-SW	Polyellipsoid headlight(s)
PFA	Particle filter system
PFI	Port fuel injection, inlet-channel injection
P-FP	p-FP: Delivery pump pressure.
PG	Phase sensor
PH	Pressure high, high pressure
PHI	phi: Greek letter used to designate angles.
PHS	Park heater system
PI	Pilot injection. See also POI, MI, and HE.
PID	Parameter identifier, part of CARB, code for current values or similar parameters, usually  proper name
P-IN	p-in: Delivery pressure
PIP	Profile ignition pickup, ignition output circuit (Ford) or Signal of Hall sensor for crankshaft RPM and position
PJ	Pilot-Jection
PKW	Passenger car
PL	Country code for Poland, or Pressure low, low pressure
PLA	Pneumatic idle increase or Pneumatic idle stop
PLD	Pump-line-nozzle, diesel injection technique (new designation is UPS)
PLR	Pneumatic idle speed control
PLU	Pierburg measurement cell, or Pierburg Aviation
PM	Pump motor
PML	Parametric steering, assisted vehicle steering. The related data (parameters) are stored  in the control unit.
PMR	Private mobile radio
PMS	Engine control with load detection via intake-manifold pressure (Mercedes)  or Inlet-channel injection
PNAB	Pneumatic adjustment device
PNABU	Pneumatic adjustment device, vacuum-operated (Bosch KH)
PNABUE	Pneumatic adjustment device, pressure-operated (Bosch KH)
PNG	Papua New Guinea
POBSY	Pedestrian protection optimised bumper system. Ford bumper system made  from energy-absorbing foam plastics to protect pedestrians.
POI	Post-injection. See also PI, MI, and HE.
POTI	Potentiometer, variable resistance
PPG	PPG module: Periphery program module; module containing control  unit diagnostic programs or other CompacSoft programs, proper name
PPM	ppm: parts-per-million, unit
PPS	Pedal position system, or Pedal position sensor
PRC	People's Republic of China
PRG	Program
PROG	Programming input
PROM	Programmable read-only memory, usually proper name
PRS	Programmed restraint system. Reduces the seat-belt tension and thus upper-body  injuries (Renault)
PS	Test step or Pump control or Horsepower, unit of work performed by motor vehicles
PSA	PEUGEOT SOCIETE AUTOMOBILE, proper name
PSD	Pump control with diagnosis or Porsche limited-slip differential, usually proper name
PSE	Pneumatic system electronics, electronically controlled pneumatic system
PSG	Pump control unit
PSI	psi: Pounds per square inch, physical unit
PSM	Porsche Stability Module. Porsche-specific designation for ESP.
PSP	Power steering pressure
PSPS	Power steering pressure switch
PSV	Partial intake-manifold pre-heating
PT	Power train
PTC	Positive temperature coefficient, thermal resistor with positive temperature coefficient , so-called cold conductor, or PTC heating element in intake manifold for delivering heat  for evaporation
PT-CAN	Power train CAN bus. High-speed CAN bus for drive-train electronics. See also  K-CAN, SI-BUS.
PTS	Park-Tronic System. Parking aid. See also PDC.
PV	Testing instruction
PVS	Vacuum switch
PWG	Pedal position sensor, usually proper name
PWL	Power window lifter
PWM	Pulse-width modulation, special signalling form used to determine pulse-duty factors  on components (for example, triggering of tank ventilation valve is usually based on  such a factor)
PWR	Pulse rectifier
PY	Paraguay
Q	Quantity, usually of fuel
Q1	Fuel quantity for cylinder 1. Similarly Q2, Q3, etc.
Q-AVG	Quantity average. Mean of (fuel) quantity of all cylinders
QB	Quality assessment
QGS	Quick glow system. Rapid pre-heating system for diesel engines.
QHS	Quick heat system. Rapid diesel pre-heating system.
QM	Quality management
Q-OVER	Q-over: Overflow quantity
QS	Quality assurance
QSF	Average function
QSL	Quasi select low
QUADR	Quadrifoglio, Alfa Romeo model designation
RA	Rear axle, or Argentina
RAIL	Common Rail, high-pressure distribution line with Common Rail diesel systems
RAM	Random access memory, read/write memory of a processor
RAS	Rear-axle steering. Actively steered rear axle used in buses, for example.
RB	Robert Bosch
RC	Remote control, or China (Taiwan)
RCA	Republic of Central Africa
RCH	Chile
RDK	Tire pressure check system, usually proper name
RDS	Rail pressure sensor or Radio data system
RDU	Tyre pressure monitoring
RDV	Reverse-flow throttle valve
RDW	Rest of the world (group in exhaust-gas classification)
RE	Right (often "re") or Inline injection pump
REA	Resonance detection
REC	Rear electrical centre (Opel)
REL	Relay
RF	Radio frequency, radio signal
RFP	Return pump
RFS	Backup light(s)
RFT	Run-flat tyre. Special tyre that can also be used in an emergency.
RG	Route guidance (Travel Pilot)
RGS	Route guidance standalone (Travel Pilot as standalone system)
RHD	Right-hand drive
RHO	rho: Greek letter, represents density (kg/m³)
RHV	Static high-voltage distribution
RI	Indonesia
RIV	Control pulse method (diesel)
RKS	Tire check system
RL RLDM	Right-hand drive Rear Left Door Module
RLFS	Fuel supply system without reverse flow
RLV	Reverse-flow valve
RM	Reference mark
RME	Rapeseed methyl ester, alternative fuel
RO	Romania
ROK	Republic of Korea
ROM	Read-only memory. Program memory of processor, or other memory, that can only be read.
RON	Research octane number, see also ROZ
ROPS	Rollover protection system. Automatically extendable rollbar (Volvo)
ROV	Rotating high-voltage distribution
ROZ	Research octane number
RP	In-line pump, or Philippines
RPA	Flat tyre indicator
RPM RRDM	Revolutions per minute Rear Right Door Module
RS	Restraint system or Rotational speed sensor
RSC	Run-flat system component. Tyres with emergency-running properties. See also RFT.
RSD	Backflow throttle
RSV	Check valve, prevents undesired reverse-flow of liquids or gases
RTI	Radio Traffic Information, Verkehrfunk
RTM	Smoke opacity measurement module, product name for exhaust-gas tester (Bosch)
RTR	Reverse-flow temperature control
RU	Soot concentration in exhaust
RUE	Soot emission
RUEF	Retrofit vehicle
RUM	Soot amount
RUV	Static high-voltage distribution, usually proper name
RW	Control travel
RWAWS	Control-travel evaluation circuit
RWD	Rear wheel drive
RWG	Control-travel sensor
RX	Receive line (contrast with TX line).
RZ	Wheel brake cylinder

S	S: Sensor, or super (premium) grade fuel, or sport program (automatic transmission),  or Sweden s: seconds
SAC	Self-adjusting clutch. Transmits only the current engine torque
SACV	Secondary air control valve
SAE	Society of Automotive Engineers, US organization that prescribes standards,  recommendations, or guidelines for technically implementing legal  requirements (such as for engine oil, error codes, data transmission, etc.)
SAM	Safety (or signal detection) and triggering module. Designation for Mercedes control unit.
SAS	Side-impact protection
SAT	Siemens adaptive transmission control
SAV	Overrun cutoff valve, or Sport activity vehicles (for example BMW X5)
SB	Star-of-injection, indicates when fuel injection actually starts (the start-of-delivery  on the other hand is the time at which the fuel pump begins to deliver), or Control  unit for start-of-injection control (diesel)
SBB	Disc-brake lining
SBC	Sensotronic Brake Control, part of EHB (electrohydraulic brake) system
SBE	Seat-occupied detection
SBK	Safety battery terminal. Part of airbag system. In the case of an accident, the battery  is rapidly disconnected from the starter cable in order to prevent short circuits  and reduce the risk of fire.
SBR	Start-of-injection control
SBS	Speech-based operation system (Porsche designation)
SCAN TOOL	Tester for reading OBD error codes and other OBD data
SCC	Safety car concept. Volvo concept for vehicle in which many safety feature s have been integrated
SCHALT	Switch
SCHR	Steps, such as with a stepping motor
SCI SCL	Smart-charged injection. Petrol direct injection (Ford) Steering Column Lock
SCP	Serial communication protocol, proper name
SCS	Stability control system. Simplified form of ESP (Mitsubishi).  Prevents vehicle tilting or skidding.
SCU	Sensor and control unit. Control unit with integrated radar sensor,  main component of ACC system.
SD	Intake manifold pressure, or Sunroof, or Injection duration, or Control unit diagnosis
SDI	Intake diesel injection
SDL	Service diagnosis line, product designation for test line (Bosch)
SDM SDM	Sunroof motor or Control unit diagnosis module Sensing and Diagnostic Module (airbag)
SDS	Intake-manifold pressure sensor
SDW	Signal from anti-theft warning system
SEC	Seconds, physical unit
SEFI	Sequential fuel injection, usually proper name
SELECT HIGH	Select-high control for commercial-vehicle ABS systems. The pressure level is geared  to the wheel running with the higher coefficient of friction.
SELECT LOW	Select-low control with commercial-vehicle ABS systems. Pressure level depends on  wheel running with the lower coefficient of friction
SET CONTROLLER	Program command related to controller
SFI	Sequential multipoint fuel injection
SFT	Short (term) fuel trim (lambda-parameter correction). See also STFT.
SG	Control unit
SGP	Singapore
SHD	Sliding or lifting sunroof
SHR	Select-high control for commercial-vehicle ABS systems. The pressure level is geared to  the wheel running with the higher coefficient of friction.
SHZ	Heated seat
SI	Speed index (code letter for speed), or Silicon
SIA	Service interval indicator. Shows the driver that oil change or annual inspection  is required, for example. See also WIV.
SI-BUS SID SIDC	Safety and information bus system. See also K-CAN and PT-CAN. System Information Display Sid Controller
SIH	Sitzheizung
SIL	Seat electrical system, left
SILA	Signal lamp
SIM	Safety information module. Component of ISIS system (BMW)
SIPS	Side-impact protection system (Volvo)
SIR	Seat electrical system, right.
SIS	Service Information System, proper name or Series repair
SKF	Spike characteristic. Relates to Porsche transmission controls.
SKO	Compressor signal
SKT	Scale units
SL	Select low
SLA	Safety lamp
SLE SLM	Secondary-air injection Shift lever Module
SLO	Slovenia
SLP	Secondary-air pump
SLR	Select-low control for commercial-vehicle ABS systems. The pressure level  is geared to the wheel running with the lower coefficient of friction.
SLS	Secondary-air system
SM	Seat memory, or Stepping motor
SME	Stepping-motor electronics
SNA	Automatic momentum utilisation
SNR	Part number or Record number
SO	Safety switch, normally closed (actuator)
SO2	Sulphur dioxide. Pungent gas causing respiratory diseases. It is thus an  aim to reduce the sulphur content in exhaust gases.
SOHC	Single overhead camshaft
SOP	Start of production
SP	Safety testing, usually in conjunction with testing of brake system
SPA SPA	Mirror drive Sonic Park Assist
SPI	Single point injection, usually proper name
SPL	Noise level, or Sound-pressure level
SPM	Mirror memory, usually proper name
SPOR	Sporadic
SPOUT	Ignition signal (EEC IV)
SPS	Solar position sensor
SPV	Injection adjustment (see also SV)
SR	Side-based control
SRA	Headlight wiper system
SRC	Source (of data or audio signals, for example)
SRE	Intake-manifold injection
SRM SRM	Headlight wiper motor Sun Roof Module
SRS	Safety restraint system (generally includes airbag and seatbelt tensioner,  normally controlled by a common control unit)
SS	Safety switch, normally open (sensor 9)
SSA	Automatic start/stop
SSD	Steel sliding sunroof
SSG	Seat control unit (Mercedes)
SSHD	Steel sliding/lifting sunroof
SSS	Stop/start system
SST	Special tool or self-supporting tyre, tyre which supports itself and features limp-home properties
SSU	Triggering device for side airbag
ST	System tester
STAE	Start external, external start switch
STAT	Static
STC	Stability and traction control
STFT	Short-term fuel trim (for lambda-parameter correction). See also SFT.
STH	Stationary-vehicle heater
STI	Self-test input signal
STM	Servomotor
STO	Self-test output signal
STOE	Stop external, external stop switch
SU	Soviet Union
SULEV	Super ultra-low emissions vehicle (group in classifying exhaust-emissions levels).  See also LEV, NLEV, ULEV, TLEV, and ZEV.
SUS	Slip threshold switchover
SUV	Sport utility vehicles. Vehicle group comprising off-road-capable, leisure-activity sport vehicles and commercial vehicles with all-wheel drive (fun vehicles). Better  suited for on-road than off-road. Examples: Mazda Tribute, Mercedes ML 320.
SV	Injection adjustment (see also SPV) or Servo valve or Start valve
SVC	Saab variable compression. The cylinder head is tilted in order to modify the compression  ratio, or Speed volume control. Speed-dependent volume control for car radios.
SVG	Seat adjustment transmission
SVM	Seat adjustment motor
SW	Headlight(s) or Software
SWA SWC	Headlight washer Steering Wheel Control
SWD	Vibration damper
SWT	Side wall torsion sensor. Detects longitudinal and transverse forces directly at the wheel  during acceleration, braking, and in curves. Currently employed for quick-reaction  ABS and ESP systems, in the future possibly for counteracting wind gusts.
SZ	Opacity number, or Coil ignition, possibly with interrupt contacts or Switching-time program (determines switching time)
T	t: (such as t-adj., time of adjustment) T: temperature (such as T-comp,  compression temperature)
T.C.S.	Ignition timing control system
T.O.C.S.	Throttle valve control system
TA	Traffic announcement, or Thorax airbag (BMW)
TAB	Test Airbag. Excitation lead for airbag system (Mazda)
T-ABGLEICH	t-adjust: time of adjustment
TAC	Test Air Conditioning. Excitation lead for air conditioner (Mazda)
TANS	Tans: Intake air temperature (in °C)
TAS	Temperature dependent control, with distributor injection pumps, or Temperature  dependent start-volume, with distributor injection pumps
TAT	Test Automatic Transmission. Excitation lead for transmission control (Mazda)
TAU	Automatic temperature system
TBB	Drum-brake shoes
TBI	Throttle body injection, central injection
TBS	Test Brake System. Excitation lead for ABS system (Mazda)
TC	Traction control, auxiliary function with ABS
TCE	Trailer central electronic, central electronics system for trailer
TCM	Transmission control module (Opel automatic-transmission control unit)
TCO	Tachograph (Mercedes)
T-COMP	T-comp: Compression temperature
TCS	Traffic centre service
TCSA	Temperature controlled spark advance
TCU	Transmission control unit
TD	TD: Time division, engine load signal tD: Transistor speed signal, square-wave signal  supplying RPM for other systems such as transmission control
TDC	Top dead centre, see also OT
TDI	Turbo diesel injection
TDS	Tank pressure sensor
TEC	Total electronic control
TEE	Tank installation unit
T-EIN	t-ein: Build-up time
TELE-AID	Telematic alarm identification on demand, accident notification
TEMP TMS	Temperature Telematics
TEMP. SCH.	Temperature switch
TEMPF	Temperature sensor
TEN	Test Engine. Excitation lead for control unit (Mazda), usually proper name
TES	Thermo-electric switch or tank ventilation system (also referred to as evaporative  emission-control regeneration system)
TEV	Tank ventilation valve or Thermostatic expansion valve (heating/air conditioning)
TF	Temperature sensor
TFA	Test of radiator fan
TFI	Electronic ignition switch (EEC)
THA	Thailand
THS	Toyota hybrid system. Hybrid of combustion and electrical drive, with electronic control.
T-HYBRID	Hybrid temperature
THZ	Tandem master cylinder. Master brake cylinder for hydraulic brakes.
TI	ti: Injection signal (t=time, i=ignition)
TID	Test identification data or Triple Info Display, driver information system in which  certain data and information is displayed
TIM	Time impulse
T-IN	T-in: Inflow temperature (actual) T-in (nom.): Nominal inflow temperature
TIPTRONIC	Porsche or VW electronic transmission control. The control can be operated via a  small device on the steering wheel.
TKRAFT	Fuel temperature (in °C)
TKU	Technical customer documentation
TL	tl: Engine load signal recorded over time TL: Partial throttle, engine operating state
TLA	Temperature dependent idle increase, with distributor injection pumps
T-LASTPUNKT	Time of load point
TLEV	Transient low-emissions vehicle (group in exhaust-emissions classification). Comprises vehicles with low emissions levels. See also LEV, NLEV, SULEV, ULEV, and ZEV.
TLK	Temperature dependent idle correction
TMB	Door module, passenger side
TMC	Traffic message channel
T-MESS	Time or duration of measurement
TMF	Door module, driver side
TMOT	Engine temperature (in °C), usually determined from coolant
TMS	Telematic system
TN	tn: Signal from ignition with inductive peaks suppressed. Used for RPM detection for  control unit and speedometer
TNA	Signal output for engine speed.
T-OFFSET	Time offset
T-OVER	T-over: Overflow temperature
TP	Throttle valve potentiometer (actuator)
TPM TPM	Tempomat (cruise control) Tyre Pressure Monitoring
TPMS	Tyre pressure monitoring system, with pressure and temperature sensors at wheel  (Opel/Teves)
TPS	Throttle position sensor
TQ	Time quantity (usually TQ signal). Fuel consumption signal.
TR	TR: RPM information, or contact roller, or Turkey tr: Calculated RPM signal
TRACS	Traction control system (Volvo)
TRUST	Trundle stability
TS	Temperature switch or Twin spark, double-spark ignition (Alfa Romeo)
TSG	Tank level sensor or Door control unit
TSH	Door lock heater
TSP	Trailer stability program, ESP type system for trailers, designed to prevent trailer  skid (Opel)
TSS	Thermal protection switch
TSU	Speedometer signal transformer
TSZ	Transistor coil ignition with discrete components
TSZ-H	Transistor coil ignition with Hall sensor
TSZ-I	Transistor coil ignition with inductive sensor
TSZ-IZA	Transistor ignition with ignition coil in distributor
TT	TT division. Black-and-white division of brake circuits: one circuit in front, one in rear.
T-TOTAL	t-total: Total measurement time
TUEV	German vehicle-inspection authority
TV	TV: Timing valve tv: Offset time of oxygen sensor control
TVA	Temperature dependent full-load stop
T-VIS	Toyota variable intake system (cut-in at 4500 rpm in 16-valve engines)
TVS	Temperature dependent vacuum switch or Thermal vacuum switch
TVSV	Temperature dependent vacuum switching valve
TWA	Twin-wheel axle. Axle with twin tires on each side.
T-WAIT	t-wait: Wait time
T-WARTE	Wait time
TWC	Three-way catalytic converter
TX	TX line: Transmission line, in contrast to RX line
TZ	Transistor coil ignition with hybrid component
TZ-H	Transistor ignition with Hall sensor
TZ-I	Transistor ignition with inductive sensor
TZS	Thermal time switch
U	Below, underneath or Voltage
UAE UAM	United Arab Emirates Ultrasonic Alarm Module
UB	Battery voltage, supply voltage at terminal 30
U-BATT	Battery voltage
UBF	Lower control panel. Near the gearshift lever or below the radio, some vehicles have  switches or buttons, such as for the rear-window defogger. These elements together  comprise a control panel, which is referred to as the lower control panel to distinguish  it from another control panel on or above the dashboard.
UBL	Brake-light voltage
UCL	Understeering control logic. ESP system used in Renault Megane.
UDB	Vacuum limiter
UD-F	Vacuum adjustment EARLY
UD-MODUL	Vacuum module. Valve for switching and measuring intake manifold pressure
UDS	Accident data memory (VDO), similar to black box in aircraft
UD-S	Vacuum adjustment LATE
UEC	Underhood Electrical Center, Opel designation for engine-compartment electronics module
UEDS	Excessive-speed switch
UEGO	Universal exhaust gas oxygen sensor, non-heated Lambda sensor
UERB	Rollbar
UEV	Excessive-flow valve
UG UHC	Lower limit Lower tolerance limit Unité Centrale d'Habitaclé (Cabin Central Processor)
UIS	Unit injection system, new designation for PDE systems (diesel injection systems  with pump-nozzle unit)
U-KAT	Unregulated catalytic converter (without oxygen sensor control)
ULEV	Ultra-low emissions vehicle (group in exhaust-gas classification). See also LEV,  NLEV, SULEV, TLEV, and ZEV.
ULW	Ultra lightweight
UM	Reversing valve (for ASR operation)
UMTS	Universal Mobile Telecommunications System. Standard for the 3rd generation of  mobile radio communications. Is to replace the analogue radio system over the long term.
UNI1	UNI2,Additional lines on universal adapter cable, used to read out flash codes or for  special purposes
UP	Unsaturated polyester. Thermosetting plastic used in body construction or to  manufacture pressure-resistant containers.
UPA	Ultrasonic parking assistant
UPS	Unit Pump System, new designation for PLD systems
URS	Rollover sensor, usually proper name
US	Designation denoting basis on U.S. emission standards
USA	United States of America
USB	Universal serial bus. The USB interface permits simple connection of various peripherals to a PC.
USG	Non-interrupting manual transmission. Two clutches (drive-off and load-shift)  enable electronically controlled driving without shifting interruptions.
USV	Change-over valve
UT	Bottom dead centre
UUV	Urban Utility Vehicle, Nutzfahrzeug für den Einsatz in der Stadt
UV	Ultraviolet. Used mostly in conjunction with light or radiation.
UVR	Voltage at valve relay
UVS	Rollbar and variable sunroof control (Mercedes)
UW	Voltage converter
UZ	Voltage after ignition, terminal 15
V	V: Volt, physical unit, or carburetor engine, or valve, or viscose, or fan, or front v:  Front, or velocity
V/MS	V/ms: volts per millisecond, unit for voltage per time.
VA	Vorderachse
VAC	Variant coding
VAF	Air-flow sensor
VAG	Volkswagen AG, vehicle maker, proper name
VAKU-SCH.	Vacuum switch
VAN	Vehicle Area Network. The VAN bus is a bus system that interconnects various  components in the vehicle. This can be a CAN bus, but it can also be another type of bus.
VANOS	Variable camshaft timing
VARILIS	Variable lighting system (Hella)
VAT	Intake-air temperature sensor
VC	Variant coding
VCV	Vacuum control valve
VD	Choke valve
VDC	Vehicle distance control or Vehicle dynamics control
VDV	Vacuum delay valve
VE	Distributor injection pump (series designation). See also VP
VERD.	Verdeck (Cabrio)
VES	Fully electronic radio ignition key
VEZ	Fully electronic ignition system
VFD	Vacuum fluorescence display
VFR	Variable focus reflector (headlight)
VGWX	Preset value if sensor fails
VIM	Vehicle immobilizer
VIN	Vehicle identification number, code stored in control unit
VIS	Variable Intake System (Rover)
VK	Valve body
VKP	Programmable variant coding
VKS	Variant coding with plug
VL	Left front, or Full load, engine operating state
VLP	Preliminary charge pump
VM	Adjustment motor or Combustion engine
VOCS	Voice control system
VP	Distributor pump (usually factory-internal designation). See also VE
VPC	Volvo Personal Communicator. SCC element with fingerprint sensor that detects the  identity of the driver and makes driver-specific adjustments.
VR	Right front or Distributor pump with radial piston
VRD	Vario nozzle, nozzle with variable radius
VRM	Valve feedback
VRS	Relay supply voltage
VSA	Vehicle stability assist. System similar to ESP.
VSC	Voltage supply control. Battery management system (Mercedes)
VSG	Composite safety glass
VSO	Vehicle speed out
VSS	Volts peak-to-peak, unit for special voltage values, measures difference between  maximum and minimum voltage levels or Vehicle speed sensor, or Vehicle security  systems
VSV	Vacuum switching valve
VT	Vacuum transducer
VTG	Variable turbine geometry. The turbine has movable guide blades, which can  be varied  depending on the operating state of the vehicle. A turbocharger with variable turbine  geometry offers the advantage that it is more responsive than a conventional  turbocharger with fixed turbine geometry.
VTV	Vacuum transmitting valve
VVA	Variable valve actuation. Variable valve control between cams and valves. Operates electrohydraulically. Duration and width of opening can be varied (Fiat, Lancia)
VVC	Variable valve control
VVL	Variable valve lift
VVW	Variable valve displacement
VW	Compensating resistor or Volkswagen, vehicle maker, proper name
VZ	Electronic ignition timing with static distribution
VZ-K	Electronic ignition timing with static distribution and knock control

W/M2	W/m². Watts per square meter. Physical unit for solar radiation intensity
WAA	Wiper blade
WALA	Safety lamp
WAN	Nigeria
WDS	World diagnostic system (Ford tester)
WE	Water injection
WEBER	Weber petrol injection
WEO	Western Europe except Germany
WFS	Immobilizer
WHA	Water-side automatic heater
WIG	Wiper pulse transmitter
WIV	Service interval extension. Under certain conditions (use of special oils, etc.), service can be performed at greater intervals. Also referred to as Longlife Service (VW, Audi).
WK	Converter clutch
WL	Warning lamp
WLR	Warmup control
WR	Warmup control or Warning lamp relay
WS	Wiper or Travel sensor
WSA	Wiper system
WSG	Separate control unit
WSH	Wiper lever
WSK	Converter clutch used in semiautomatic transmission
WSKS	Converter clutch switch
WSM	Wiper motor
WSS	Window screen system. A type of night-vision unit (DaimlerChrysler). Supports driver in night driving by making an infrared image of what is visible  through the windscreen and displaying it on a separate screen.
WSZ	AC ignition
WT	Heat exchanger
WTF	Water temperature sensor
WUEK	Eigentlich WÜK, Wandlerüberbrückungskupplung, verhindert Schlupf im  Drehmomentwandler
X	X division. Diagonal division of brake circuits: one circuit for left-front and right-rear,  and one circuit for right-front and left-rear.
XE	Extreme economy. Selection option for extremely economical driving with automatic  transmissions
XS	Extreme sport. Selection option for extremely sporty driving with automatic transmissions
YRS	Yaw rate sensor. Component of ESP system
YV	Venezuela
Z.Z.	Currently, at the moment
ZA	Ignition suppression or South Africa
ZAB	Central display and operating unit for information
ZAS	Cylinder shutoff
ZBR	Central vehicle computer
ZDA	Intermediate RPM stop
ZDE	Intermediate RPM adjuster
ZDR	Intermediate RPM control
ZDT	Cyclical nozzle-exchange procedure
ZE	Central injection or Central electronics
ZEE	Central injection unit, Mono-Jetronic
ZEV	Zero-emissions vehicle. Vehicle producing no exhaust gases. See also LEV, NLEV,  SULEV, TLEV, and ULEV.
ZGM	Central gateway module
ZGW	Central gateway. Computer that connects and controls data exchange between  two networks
ZK	Ignition circuit (airbag system)
ZKO	Ignition capacitor
ZLS	Auxiliary air slider
ZLV	Auxiliary air valve
ZME	Trim unit. Control unit for the high-pressure pump (such as CP3) of a  Common Rail system. Measures the fuel quantity fed to the pump.
ZMS	Two-mass flywheel
ZNPB	Central delivery volume normal test stand (special tester for injection pumps)
ZOS	Zero offset disc brake (no residual drag moment)
ZOT	Cylinder top dead centre
ZRE	Zaire
ZS	Ignition coil
ZU	Intermediate inspection
ZUS.LUFTP.	Auxiliary air pump (secondary air injection)
ZV	Central locking or Ignition distributor or Ignition timing adjustment
ZVM	Central locking module
ZVN	Central valve for level adjustment
ZW	Between
ZWD	Two-coil actuator (servomotor with two coils)
ZWG	Intermediate transmission
ZWS	Accessory for immobilizer
ZWV	Ignition timing adjustment
ZYL	Cylinder