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.
- P04D2Generic · PowertrainEGR Temperature Sensor C Circuit Intermittent/Erratic
- P04D3Generic · PowertrainExhaust Brake Input Circuit
- P04D4Generic · PowertrainExhaust Brake Input Circuit Range/Performance
- P04D5Generic · PowertrainExhaust Brake Input Circuit Low
- P04D6Generic · PowertrainExhaust Brake Input Circuit High
- P04D7Generic · PowertrainExhaust Brake Input Circuit Intermittent/Erratic
- P04D8Generic · PowertrainExcessive Time To Enter Closed Loop EGR Control
- P04D9Generic · PowertrainClosed Loop EGR Control At Limit - Flow Too Low
- P04DAGeneric · PowertrainClosed Loop EGR Control At Limit - Flow Too High
- P04DBGeneric · PowertrainCrankcase Ventilation System Disconnected
- P04DCGeneric · PowertrainFuel Fill Door Position Sensor/Switch Circuit Range/Performance
- P04DDGeneric · PowertrainCold Start EGR A Flow Insufficient Detected
- P04DEGeneric · PowertrainCold Start EGR A Flow Excessive Detected
- P04DFGeneric · PowertrainEVAP System Purge Control Valve A Performance/Stuck Open
- P04E0Generic · PowertrainEVAP System Purge Control Valve A Stuck Closed
- P04E1Generic · PowertrainCrankcase Ventilation Hose Connection Sensor Circuit
- P04E2Generic · PowertrainCrankcase Ventilation Hose Connection Sensor Circuit Low
- P04E3Generic · PowertrainCrankcase Ventilation Hose Connection Sensor Circuit High
- P04E4Generic · PowertrainCrankcase Ventilation Hose Connection Sensor Circuit Intermittent/Erratic
- P04E5Generic · PowertrainEGR Temperature Sensor D Circuit
- P04E6Generic · PowertrainEGR Temperature Sensor D Circuit Range/Performance
- P04E7Generic · PowertrainEGR Temperature Sensor D Circuit Low
- P04E8Generic · PowertrainEGR Temperature Sensor D Circuit High
- P04E9Generic · PowertrainEGR Temperature Sensor D Circuit Intermittent/Erratic
- P04EAGeneric · PowertrainEVAP System Small Leak Detected - Fuel Tank Side
- P04EBGeneric · PowertrainEVAP System Small Leak Detected - Fresh Air Side
- P04ECGeneric · PowertrainEVAP System Large Leak Detected - Fuel Tank Side
- P04EDGeneric · PowertrainEVAP System Large Leak Detected - Fresh Air Side
- P04EEGeneric · PowertrainEVAP System Very Small Leak Detected - Fuel Tank Side
- P04EFGeneric · PowertrainEVAP System Very Small Leak Detected - Fresh Air Side
