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.
- P2506Generic · PowertrainECM/PCM Power Input Signal Range/Performance
- P2507Generic · PowertrainECM/PCM Power Input Signal Low
- P2508Generic · PowertrainECM/PCM Power Input Signal High
- P2509Generic · PowertrainECM/PCM Power Input Signal Intermittent
- P2509Audi · PowertrainPowertrain Control Module (PCM) failure, Powertrain Control Module (PCM) power relay failure, Wiring issue
- P250AGeneric · PowertrainEngine Oil Level Sensor Circuit
- P250BGeneric · PowertrainEngine Oil Level Sensor Circuit Range/Performance
- P250CGeneric · PowertrainEngine Oil Level Sensor Circuit Low
- P250CAudi · PowertrainOil level sensor failure, Powertrain Control Module (PCM) failure, Wiring issue
- P250DGeneric · PowertrainEngine Oil Level Sensor Circuit High
- P250EGeneric · PowertrainEngine Oil Level Sensor Circuit Intermittent/Erratic
- P250FGeneric · PowertrainEngine Oil Level Too Low
- P2510Generic · PowertrainECM/PCM Power Relay Sense Circuit Range/Performance
- P2511Generic · PowertrainECM/PCM Power Relay Sense Circuit Intermittent
- P2512Generic · PowertrainEvent Data Recorder Request Circuit/ Open
- P2513Generic · PowertrainEvent Data Recorder Request Circuit Low
- P2514Generic · PowertrainEvent Data Recorder Request Circuit High
- P2515Generic · PowertrainA/C Refrigerant Pressure Sensor B Circuit
- P2516Generic · PowertrainA/C Refrigerant Pressure Sensor B Circuit Range/Performance
- P2517Generic · PowertrainA/C Refrigerant Pressure Sensor B Circuit Low
- P2518Generic · PowertrainA/C Refrigerant Pressure Sensor B Circuit High
- P2519Generic · PowertrainA/C Request A Circuit
- P251AGeneric · PowertrainPTO Enable Switch Circuit/Open
- P251BGeneric · PowertrainPTO Enable Switch Circuit Low
- P251CGeneric · PowertrainPTO Enable Switch Circuit High
- P251DGeneric · PowertrainPTO Engine Shutdown Circuit/Open
- P251EGeneric · PowertrainPTO Engine Shutdown Circuit Low
- P251FGeneric · PowertrainPTO Engine Shutdown Circuit High
- P2520Generic · PowertrainA/C Request A Circuit Low
- P2521Generic · PowertrainA/C Request A Circuit High
