DTC codes
Look up an OBD-II fault code: what it means on every car or on your make, and how to track it down.
How to read a code
- P
- SystemPowertrain
- 0
- Defined bySAE, the same on every car
- 4
- AreaAuxiliary emission controls
- 20
- FaultThe specific fault in that area
Read the code
Note every stored and pending code your scanner shows, such as P0420.
Find it
Search by code or by words. For a manufacturer code (P1, B1, C1, U1) pick your make: its meaning differs by make.
Open the code
Its page explains the symptoms, likely causes, the checks to run and the fixes.
- P20C2Generic · PowertrainReductant Heater C Control Circuit Performance
- P20C3Generic · PowertrainReductant Heater C Control Circuit Low
- P20C4Generic · PowertrainReductant Heater C Control Circuit High
- P20C5Generic · PowertrainReductant Heater D Control Circuit/Open
- P20C6Generic · PowertrainReductant Heater D Control Circuit Performance
- P20C7Generic · PowertrainReductant Heater D Control Circuit Low
- P20C8Generic · PowertrainReductant Heater D Control Circuit High
- P20C9Generic · PowertrainReductant Control Module Requested MIL Illumination
- P20CAGeneric · PowertrainReductant Injection Air Pressure Leakage
- P20CBGeneric · PowertrainExhaust Aftertreatment Fuel Injector A Control Circuit/Open
- P20CCGeneric · PowertrainExhaust Aftertreatment Fuel Injector A Control Performance
- P20CDGeneric · PowertrainExhaust Aftertreatment Fuel Injector A Control Circuit Low
- P20CEGeneric · PowertrainExhaust Aftertreatment Fuel Injector A Control Circuit High
- P20CFGeneric · PowertrainExhaust Aftertreatment Fuel Injector A Stuck Open
- P20D0Generic · PowertrainExhaust Aftertreatment Fuel Injector A Stuck Closed
- P20D1Generic · PowertrainExhaust Aftertreatment Fuel Injector B Control Circuit/Open
- P20D2Generic · PowertrainExhaust Aftertreatment Fuel Injector B Control Performance
- P20D3Generic · PowertrainExhaust Aftertreatment Fuel Injector B Control Circuit Low
- P20D4Generic · PowertrainExhaust Aftertreatment Fuel Injector B Control Circuit High
- P20D5Generic · PowertrainExhaust Aftertreatment Fuel Injector B Stuck Open
- P20D6Generic · PowertrainExhaust Aftertreatment Fuel Injector B Stuck Closed
- P20D7Generic · PowertrainExhaust Aftertreatment Fuel Supply Control Circuit/Open
- P20D8Generic · PowertrainExhaust Aftertreatment Fuel Supply Control Performance
- P20D9Generic · PowertrainExhaust Aftertreatment Fuel Supply Control Circuit Low
- P20DAGeneric · PowertrainExhaust Aftertreatment Fuel Supply Control Circuit High
- P20DBGeneric · PowertrainExhaust Aftertreatment Fuel Supply Control Stuck Open
- P20DCGeneric · PowertrainExhaust Aftertreatment Fuel Supply Control Stuck Closed
- P20DDGeneric · PowertrainExhaust Aftertreatment Fuel Pressure Sensor Circuit
- P20DEGeneric · PowertrainExhaust Aftertreatment Fuel Pressure Sensor Circuit Range/Performance
- P20DFGeneric · PowertrainExhaust Aftertreatment Fuel Pressure Sensor Circuit Low
