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.
- P23C4Generic · PowertrainEngine Coolant Bypass Valve C Position Sensor Circuit Low
- P23C5Generic · PowertrainEngine Coolant Bypass Valve C Position Sensor Circuit High
- P23C6Generic · PowertrainEngine Coolant Bypass Valve C Control Circuit Driver Current/Temperature Too High
- P23C7Generic · PowertrainFuel Heater Control Module Power Control Circuit/Open
- P23C8Generic · PowertrainFuel Heater Control Module Power Control Circuit Low
- P23C9Generic · PowertrainFuel Heater Control Module Power Control Circuit High
- P23CAGeneric · PowertrainFuel Rail Heater Control Circuit/Open
- P23CBGeneric · PowertrainFuel Rail Heater Control Circuit Low
- P23CCGeneric · PowertrainFuel Rail Heater Control Circuit High
- P23CDGeneric · PowertrainFuel Heater Control Module Feedback Signal/Open
- P23CEGeneric · PowertrainFuel Heater Control Module Feedback Signal Performance
- P23CFGeneric · PowertrainFuel Heater Control Module Feedback Signal Circuit Low
- P23D0Generic · PowertrainFuel Heater Control Module Feedback Signal Circuit High
- P23D1Generic · PowertrainCylinder 1 Fuel Heater Control Circuit/Open
- P23D2Generic · PowertrainCylinder 1 Fuel Heater Control Circuit High
- P23D3Generic · PowertrainCylinder 1 Fuel Heater Control Circuit Low
- P23D4Generic · PowertrainCylinder 1 Fuel Heater Performance
- P23D5Generic · PowertrainCylinder 2 Fuel Heater Control Circuit/Open
- P23D6Generic · PowertrainCylinder 2 Fuel Heater Control Circuit High
- P23D7Generic · PowertrainCylinder 2 Fuel Heater Control Circuit Low
- P23D8Generic · PowertrainCylinder 2 Fuel Heater Performance
- P23D9Generic · PowertrainCylinder 3 Fuel Heater Control Circuit/Open
- P23DAGeneric · PowertrainCylinder 3 Fuel Heater Control Circuit High
- P23DBGeneric · PowertrainCylinder 3 Fuel Heater Control Circuit Low
- P23DCGeneric · PowertrainCylinder 3 Fuel Heater Performance
- P23DDGeneric · PowertrainCylinder 4 Fuel Heater Control Circuit/Open
- P23DEGeneric · PowertrainCylinder 4 Fuel Heater Control Circuit High
- P23DFGeneric · PowertrainCylinder 4 Fuel Heater Control Circuit Low
- P23E0Generic · PowertrainCylinder 4 Fuel Heater Performance
- P23E1Generic · PowertrainEGR C Control Circuit/Open
