Automotive OBD II Dictionary

Approved Abbreviated Terms in Common Use Around Automotive OBD:

The acronyms in this list are referenced in SAE J1930 or are referenced in various OBD or emission regulations. CARB and EPA OBD regulations require that acronyms, definitions and abbreviations be formatted according to SAE J1930.

A
  • AAT……………….Ambient Air Temperature
  • AB&T or ABT……………Averaging Banking and Trading
  • ABS………………Anti-lock Braking System
  • ACC………………Adaptive Cruise Control
  • ADP……………….Alternative Durability Procedure
  • AECD…………….Auxiliary Emission Control Device
  • AECS…………….Auxiliary Emissions Control Strategy (The EU term for AECD)
  • AES……………..Auxiliary Emission Strategy
  • AIR……………….Secondary Air Injection
  • ALVW …………..Adjusted Loaded Vehicle Weight
  • APP………………Accelerator Pedal Position
  • ASIC……………Application Specific Integrated Circuit
  • ASIL……………..Automotive Safety Integrity Level
  • ASM……………..Acceleration Simulation Mode
  • AT-PZEV………..Advanced Technology Partial Zero Emission Vehicle
  • ATDC…………..After Top Dead Center
  • AWD…………….All Wheel Drive
  • A/C………………Air Conditioning
  • A/F……………….Air Fuel Ratio
  • A/T……………….Automatic Transmission

B
  • BARO……………Barometric Pressure
  • ВСМ……………..Body Control Module
  • BECS……………Base Emissions Control Strategy
  • BES………………Base Emission Strategy
  • BEV ……………..Battery Electric Vehicle
  • BEVx ……………Battery Electric Vehicle with Range Extender

C
  • CAA………………Clean Air Act
  • CAC………………Charge Air Cooler
  • CAFÉ…………….Corporate Average Fuel Economy
  • CALID……………Calibration Identification number
  • CAN………………Controller Area Network
  • CCM………………Comprehensive Component Monitoring
  • CCR………………California Code of Regulations
  • CFR………………Code of Federal Regulations – US
  • CFV……………….Clean Fuel Vehicle
  • CI………………….Compression Ignition
  • CKP……………….Crankshaft Position
  • СМР……………….Camshaft Position
  • CMVR…………….Central Motor Vehicle Rules – automotive industry regulations in India
  • CNG………………Compressed Natural Gas
  • CO…………………Carbon Monoxide
  • COP……………….Conformity of Production
  • CPU………………..Central Processing Unit
  • CRC………………..Cyclic Redundancy Check
  • CSERS…………….Cold Start Emission Reduction Strategy
  • CVN…………………Calibration Verification Number
  • CVS…………………Constant Volume Sampler
  • CVT…………………Continuously Variable Transmission
  • CY……………………Calendar Year

D
  • DEF…………………Diesel Exhaust Fluid
  • DF…………………..Deterioration Factor
  • DFI………………….Direct Fuel Injection
  • DFSO………………Deceleration Fuel Shut Off
  • DI……………………Distributor Ignition
  • DID…………………Data Identifier
  • DLC…………………Data Link Connector
  • DM…………………..Diagnostic Message
  • DOC………………..Diesel Oxidation Catalyst
  • DOR………………..Direct Ozone Reduction
  • DPF…………………Diesel Particulate Filter
  • DTC…………………Diagnostic Trouble Code

E
  • ECM………………..Engine Control Module
  • ECT…………………Engine Coolant Temperature
  • ECU………………..Electronic Control Unit
  • EEPROM…………Electrically Erasable Programmable Read Only Memory
  • EGR………………..Exhaust Gas Recirculation
  • EGT…………………Exhaust Gas Temperature
  • EI……………………Electronic Ignition
  • EI-ACED…………..Emission Increasing Auxiliary Emission Control Device
  • EMD………………..Engine Manufacturer Diagnostics
  • EMI………………….Electro-Magnetic Interference
  • EO………………….Engine Out
  • EO………………….Executive Officer
  • EOBD……………..European On-Board Diagnostics
  • EOP………………..Engine Oil Pressure
  • EOT………………..Engine Oil Temperature
  • ESC………………..European Stationary Cycle
  • ESC………………..Electronic Stability Control
  • ESN………………..Engine Serial Number
  • ESS………………..Energy Storage System
  • ETC………………..European Transient Cycle
  • EVAP……………….Evaporative Emissions
  • EWMA……………..Exponentially Weighted Moving Average

 

F
  • FCV…………………Fuel Cell Vehicle
  • FEL…………………Family Emission Limit
  • FF…………………..Freeze Frame
  • FFV………………..Flexible Fuel Vehicle
  • FMEA……………..Failure Mode and Effects Analysis
  • FMI…………………Failure Mode Indicator
  • FT…………………..Fuel Trim
  • FTP…………………Federal Test Procedure
  • FWD……………….Front Wheel Drive

G
  • GDI………………..Gasoline Direct Injection
  • GHG………………Green House Gas
  • GTR……………….Global Technical Regulations – United Nations regulations
  • GVWR…………….Gross Vehicle Weight Rating

H
  • HC…………………Hydrocarbon
  • HCCI………………Homogeneous Charge Compression Ignition
  • HCHO……………..Formaldehyde
  • HD………………….Heavy Duty
  • HDDE……………..Heavy Duty Diesel Engine
  • HD OBD………….Heavy Duty OBD
  • HEV………………..Hybrid Electric Vehicle
  • HO2S………………Heated Oxygen Sensor
  • HVAC………………Heating, Ventilation, and Air Conditioning
  • HWFET……………Highway Fuel Economy Test

I
  • IAC…………………Idle Air Control
  • IAT…………………Intake Air Temperature
  • IRAF……………….Infrequent Regeneration Adjustment Factor
  • JUMPR…………..In-use Performance Monitoring Ratio
  • I/M…………………Inspection and Maintenance
  • IPC………………..Instrument Panel Cluster
  • IUPR………………In-Use Performance Ratio (European reference)

J
  • JOBD……………..Japanese On-Board Diagnostics

K
  • KAM……………….Keep Alive Memory
  • KOEO……………..Key-On Engine Off
  • KOER……………..Key-On Engine Running
  • KS………………….Knock Sensor

L
  • LDT…………………Light Duty Truck
  • LDV…………………Light Duty Vehicle
  • LEV…………………Low Emissions Vehicle
  • LNG………………..Liquefied Natural Gas
  • LNT…………………Lean NOx Trap
  • LPG………………..Liquefied Petroleum Gas
  • LVW………………..Loaded Vehicle Weight

M
  • MAF………………..Mass Air Flow
  • MAP………………..Manifold Absolute Pressure
  • MDPV……………..Medium Duty Passenger Vehicle
  • MDV……………….Medium Duty Vehicle
  • MI………………….Malfunction Indicator – European reference for MIL
  • MIL…………………Malfunction Indicator Light
  • M/T…………………Manual Transmission
  • MY…………………Model Year

N
  • NAC……………….Nitrogen Oxides Adsorber Catalyst
  • NEDC…………….New European Driving Cycle
  • NGV……………….Natural Gas Vehicle
  • NMHC…………….Non-Methane Hydrocarbon
  • NMOG…………….Non-Methane Organic Gases
  • NOx……………….Oxides of Nitrogen
  • NTE……………….Not To Exceed
  • NVH……………….Noise Vibration and Harshness
  • NVLD……………..Natural Vacuum Leak Detection
  • NVRAM…………..Non-Volatile Random Access Memory

O
  • OBD……………..On Board Diagnostics
  • OBM……………..On Board Measurement
  • ODX………………Open Diagnostic Exchange
  • OEM……………..Original Equipment Manufacturer
  • ORVR……………On Board Refueling Vapor Recovery

P
  • PC…………………Passenger Car
  • PCM………………Powertrain Control Module
  • PCV ………………Positive Crankcase Ventilation
  • PEMS ……………Portable Emission Measurement System
  • PGN………………Parameter Group Number
  • PHEV……………..Plug-in Hybrid Electric Vehicle
  • PI………………….Positive Ignition
  • PID………………..Parameter Identifier
  • PM…………………Particulate Matter
  • PN…………………Particulate Number
  • PNP……………….Park/Neutral Position
  • PDTC……………..Permanent Diagnostic Trouble Code
  • PTO……………….Power Takeoff
  • PVE………………..Production Vehicle Evaluation
  • PWM………………Pulse Width Modulation
  • RZEV……………..Partial Zero Emission Vehicle

R
  • RAF………………..Reactivity Adjustment Factor
  • RAM……………….Random Access Memory
  • RDE……………….Real Driving Emissions
  • RFI…………………Radio Frequency Interference
  • RMI………………..Repair and Maintenance Information, European version of SIR
  • ROM………………Read Only Memory
  • RPM………………Revolutions per Minute
  • RSC ……………..Roll Stability Control
  • RVP……………….Reid Vapor Pressure
  • RWD……………..Rear Wheel Driver

S
  • SC………………..Supercharger
  • SCR………………Selective Catalytic Reduction
  • SCO3…………….Supplemental Federal Test Procedure with air conditioning
  • SEA……………….Selective Enforcement Audit
  • SET……………….Supplemental Emission Test
  • SFTP……………..Supplemental FTP
  • SHED…………….Sealed Housing for Evaporative Emission Determination
  • SIR………………..Service Information Rule
  • SOC………………Battery State of Charge
  • SOx……………….Sulfur Oxides
  • SPN ………………Suspect Parameter Number
  • SULEV……………Super Ultra Low Emissions Vehicle

T
  • TA………………….Type Approval
  • TC………………….Turbocharger
  • TCM……………….Transmission Control Module
  • TCMV……………..Technical Committee Motor Vehicles (EU)
  • THC……………….Total Hydrocarbons
  • TPS………………..Throttle Position Sensor
  • TWC……………….Three-Way Catalyst
  • TZEV………………Transitional Zero Emission Vehicle

U
  • UC………………..Unified Cycle
  • UDS………………Unified Diagnostic Services
  • UDDS…………….Urban Dynamometer Driving Cycle
  • ULEV……………..Ultra Low Emissions Vehicle
  • ULSD……………..Ultra Low Sulfur Diesel
  • US06………………Aggressive High Speed Driving Cycle

V
  • VIN…………………Vehicle Identification Number
  • VGT………………..Variable Geometry Turbo
  • VSS………………..Vehicle Speed Sensor
  • VVL…………………Variable Valve Lift
  • VVT…………………Variable Valve Timing
  • VMT………………..Vehicle Miles Traveled

W
  • WHDC…………….World Harmonized Driving Cycle
  • WHSC…………….World Harmonized Stationary Cycle
  • WHTC…………….World Harmonized Transient Cycle
  • WIF………………..Water In Fuel
  • WLTR……………..Worldwide Harmonized Light Vehicles Test Procedure
  • WOT……………….Wide Open Throttle
  • WR-HO2S………..Wide Range Heated Oxygen Sensor
  • WWH-OBD………World Wide Harmonized On-Board Diagnostics

Z
  • ZEV…………………Zero Emission Vehicle

Alternate Abbreviated Terms in Common Use Around Automotive OBD

The acronyms in this list are commonly used terms; however, they are not referenced in emission or OBD regulations and sometimes even conflict with SAE J1930 acronyms (as indicated below).

A
  • ACM………………Aftertreatment Control Module – J1930 preferred: EACM Exhaust Aftertreatment Control Module
  • AdBlue…………..Trademarked name for Diesel Exhaust Fluid – J1930 preferred: DEF Diesel Exhaust Fluid
  • AFM………………Air Flow Meter – J1930 preferred: MAF Sensor Mass Air Flow Sensor
  • AMOX…………….Ammonia Oxidation – J1930 preferred: NH30C Ammonia Oxidation Catalyst
  • ASOV………………Air Shut Off Valve
  • AMT…………………Automated Manual Transmission
  • APU………………..Auxiliary Power Unit
  • AWL………………..Amber Warning Lamp

 

C
  • CCC………………..Close Coupled Catalyst
  • CCV…………………Closed Crankcase Ventilation
  • CEGR………………Cooled Exhaust Gas Recirculation
  • CD…………………..Charge Depleting
  • CI…………………….Charge Increasing
  • CN6………………….China 6
  • CLCS……………….Closed Loop Control Strategy
  • COP…………………Col On Plug
  • CS…………………..Charge sustaining

D
  • DCU………………..Dosing Control Unit – J1939 preferred: FACM Fuel Additive Control Module
  • DEC……………….Diagnostic or Emission Critical (e.g. DECLECU)
  • DeNOx……………NOx Reduction Function
  • DeSOX……………Sulfur Oxide Reduction/Regeneration

 

E

EBV……………….EGR Bypass Valve-J1930 preferred: EGRBV Exhaust Gas Recirculation Bypass Valve

EONV……………Engine Off Natural Vacuum

EPS……………..Engine Position Sensor – J1930 preferred: CMP Camshaft Position

ESS……………..Engine Speed Sensor – J1930 preferred:CKP Crankshaft Position

EUL……………..End of Useful Life – also referred to as Full Useful Life in the EPA emission regs   FUL

 

F
  • FAF……………….Fresh Aik Flow
  • FUL………………Full UsefunLife – also referred to as EUL (End of UsefunLife)

 

G
  • GPS……………..Global Positioning System
  • GST………………Generic Scan Tool

 

H
  • HDOH…………..Heavy Duty On-Highway (used to distinguish >14,000lb GVWR from lower weight vehicles and from off highway)
  • HPCR…………..High Pressure Common Rail

 

I

 

L
  • LDP……………..Leak Detection Pump
  • LNT………………Lean NOx Trap

 

O
  • OBDEL………….OBD Emissions Limit Same as OTL
  • OC………………..Open Circuit
  • OCV………………Open Crankcase Ventilation
  • OOR……………..Out of Range
  • OORH……………Out of Range High
  • OORL…………….Out of Range Low
  • OTL……………….OBD Threshold Limit Same as OBDEL

 

P
  • PDTC…………….Permanent DTC

 

R
  • RDP……………….Reductant Delivery Performance
  • RMC-SET………..Ramped Mode Cycle – SupplementalEmissions Test
  • RSL……………….Red Stop Lamp

 

S
  • STB………………Short To Battery
  • STG………………Short To Ground

 

T
  • TLA……………….Three Letter Acronym
  • TSB………………Technical Service Bulletin

 

U
  • UQS……………..Urea Quality Sensor – J1930 preferred: RQS Reductant Quality Sensor
  • UUAA……………Used Up All Adjustment UUAAA………….Used Up All Adjustment Allowed

 

W
  • WPA…………….Worst Performing Acceptable

Regulatory and Other Organizations

The acronyms in this list are the name of regulatory or other organizations that regulate or interact with automotive manufacturers.

US ORGANIZATIONS
  • ARB……………..Air Resources Board, see also CARB
  • BAR……………..Bureau of Automotive Repair
  • CARB…………..California Air Resources Board
  • EPA……………..Environmental Protection Agency
  • ETI………………Equipment and Tool Institute
  • MISRA………….Motor Industry Software Reliability Association
  • MVEG…………..Motor Vehicle Emissions Group
  • OAL……………..Office of Administrative Law, CA Agency
  • SCAQMD……….South Coast Air Quality Management District – California

 

CHINESE ORGANIZATIONS

 

  • BEPB…………..Beijing Environmental Protection Bureau
  • CATARC………..China Automobile Technical and Research Center
  • CCC…………….China Compulsory Certification
  • CNCA…………..Certification and Accreditation Administration
  • CQC…………….China Quality Certification Center (Part of CNCA China)
  • CVTSC………….China Vehicle Technology Service Center (Part of MIIT China)
  • EPB………………Environmental Protection Bureau
  • MEP……………..Ministry of Environmental Protection
  • MIIT………………Ministry of Industry and Information Technology
  • VECC……………Vehicle Emission Control Center  (Part of MEP China)

 

EUROPEAN ORGANIZATIONS
  • ACEA……………European Automobile Manufacturers Association
  • CCFA……………French Automobile Manufacturers Association (Comité des Constructeurs Français d’Automobiles)
  • ECE…………….Economic Commission for Europe
  • EU………………European Union
  • GRPE…………..Working Party on Pollution and Energy (Group de Rapporteurs sur  la Pollution et l’ Énergie)
  • ISO………………International Organization for  Standardization
  • OICA…………….Organisation Internationalles Constructeurs des Automobiles
  • SMM&T………….Society of Motor Manufacturers and Traders
  • UN………………..United Nations
  • VDA……………..German Automobile Manufacturers Association (Verband der deutschen Automobilindustrie)

 

SOUTH AMERICAN ORGANIZATIONS
  • CONAMA……….Comision Nacional del Medio Ambiente – Chilean National Commission for the Environment
  • IBAMA……………Instituto Brasileiro do Meio Ambiente E Dos Recursos Naturais Renováveis – Brazil Environmental Agency

EUROPEAN COMMITTEES

AND MEETINGS

 

  • MVEG…………..Motor Vehicles Emissions Group
  • TCMV……………Technical Committee Motor Vehicles

 

NGO – NON-GOVERNMENTAL ORGANIZATIONS
  • DUH……………..Deutsche Umwelthilfe e.V.
  • ICCT……………..International Council on Clean Transportation