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.
- P04B4Generic · PowertrainRefueling Vapor Control Valve Stuck Closed
- P04B5Generic · PowertrainFuel Fill Door Stuck Open
- P04B6Generic · PowertrainFuel Fill Door Stuck Closed
- P04B7Generic · PowertrainFuel Fill Door Position Sensor/Switch Circuit Intermittent/Erratic
- P04B8Generic · PowertrainFuel Fill Door Position Sensor/Switch Circuit
- P04B9Generic · PowertrainFuel Fill Door Position Sensor/Switch Circuit Low
- P04BAGeneric · PowertrainFuel Fill Door Position Sensor/Switch Circuit High
- P04BBGeneric · PowertrainFuel Fill Door Lock Control Circuit/Open
- P04BCGeneric · PowertrainFuel Fill Door Lock Control Range/Performance
- P04BDGeneric · PowertrainFuel Fill Door Lock Control Circuit Low
- P04BEGeneric · PowertrainFuel Fill Door Lock Control Circuit High
- P04BFGeneric · PowertrainFuel Fill Door Unlock Control Circuit/Open
- P04C0Generic · PowertrainFuel Fill Door Unlock Control Range/Performance
- P04C1Generic · PowertrainFuel Fill Door Unlock Control Circuit Low
- P04C2Generic · PowertrainFuel Fill Door Unlock Control Circuit High
- P04C3Generic · PowertrainFuel Fill Door Lock Position Sensor/Switch Circuit
- P04C4Generic · PowertrainFuel Fill Door Lock Position Sensor/Switch Circuit Range/Performance
- P04C5Generic · PowertrainFuel Fill Door Lock Position Sensor/Switch Circuit Low
- P04C6Generic · PowertrainFuel Fill Door Lock Position Sensor/Switch Circuit High
- P04C7Generic · PowertrainFuel Fill Door Lock Position Sensor/Switch Circuit Intermittent/Erratic
- P04C8Generic · PowertrainFuel Fill Door Open Request Sensor/Switch Circuit
- P04C9Generic · PowertrainFuel Fill Door Open Request Sensor/Switch Performance/Stuck Off
- P04CAGeneric · PowertrainFuel Fill Door Open Request Sensor/Switch Circuit Low
- P04CBGeneric · PowertrainFuel Fill Door Open Request Sensor/Switch Circuit High
- P04CCGeneric · PowertrainFuel Fill Door Open Request Sensor/Switch Circuit Intermittent/Erratic
- P04CDGeneric · PowertrainFuel Fill Door Open Request Sensor/Switch Stuck On
- P04CEGeneric · PowertrainEGR Temperature Sensor C Circuit
- P04CFGeneric · PowertrainEGR Temperature Sensor C Circuit Range/Performance
- P04D0Generic · PowertrainEGR Temperature Sensor C Circuit Low
- P04D1Generic · PowertrainEGR Temperature Sensor C Circuit High
