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.
- P20E0Generic · PowertrainExhaust Aftertreatment Fuel Pressure Sensor Circuit High
- P20E1Generic · PowertrainExhaust Aftertreatment Fuel Pressure Sensor Circuit Intermittent/Erratic
- P20E2Generic · PowertrainExhaust Gas Temperature Sensor 1/2 Correlation Bank 1
- P20E3Generic · PowertrainExhaust Gas Temperature Sensor 1/3 Correlation Bank 1
- P20E4Generic · PowertrainExhaust Gas Temperature Sensor 2/3 Correlation Bank 1
- P20E5Generic · PowertrainExhaust Gas Temperature Sensor 1/2 Correlation Bank 2
- P20E6Generic · PowertrainReductant Injection Air Pressure Too Low
- P20E7Generic · PowertrainReductant Injection Air Pressure Too High
- P20E8Generic · PowertrainReductant Pressure Too Low
- P20E9Generic · PowertrainReductant Pressure Too High
- P20EAGeneric · PowertrainReductant Control Module Power Relay De-Energized Performance - Too Early
- P20EBGeneric · PowertrainReductant Control Module Power Relay De-Energized Performance - Too Late
- P20ECGeneric · PowertrainSCR NOx Catalyst - Over Temperature Bank 1
- P20EDGeneric · PowertrainSCR NOx Pre-Catalyst - Over Temperature Bank 1
- P20EEGeneric · PowertrainSCR NOx Catalyst Efficiency Below Threshold Bank 1 Catalyst 1
- P20EFGeneric · PowertrainSCR NOx Pre- Catalyst Efficiency Below Threshold Bank 1
- P20F0Generic · PowertrainSCR NOx Catalyst - Over Temperature Bank 2
- P20F1Generic · PowertrainSCR NOx Pre-Catalyst - Over Temperature Bank 2
- P20F2Generic · PowertrainSCR NOx Catalyst Efficiency Below Threshold Bank 2
- P20F3Generic · PowertrainSCR NOx Pre- Catalyst Efficiency Below Threshold Bank 2
- P20F4Generic · PowertrainReductant Consumption Too Low
- P20F5Generic · PowertrainReductant Consumption Too High
- P20F6Generic · PowertrainReductant Injection Valve Stuck Open Bank 1 Unit 1
- P20F7Generic · PowertrainReductant Injection Valve Stuck Open Bank 2 Unit 1
- P20F8Generic · PowertrainIntake Manifold Runner Control Circuit Performance Bank 1
- P20F9Generic · PowertrainIntake Manifold Runner Control Circuit Performance Bank 2
- P20FAGeneric · PowertrainReductant Pump B Control Circuit/Open
- P20FBGeneric · PowertrainReductant Pump B Control Performance/Stuck Off
- P20FCGeneric · PowertrainReductant Pump B Control Circuit Low
- P20FDGeneric · PowertrainReductant Pump B Control Circuit High