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.
- P043CGeneric · PowertrainCatalyst Temperature Sensor Circuit Low Bank 2 Sensor 2
- P043DGeneric · PowertrainCatalyst Temperature Sensor Circuit High Bank 2 Sensor 2
- P043EGeneric · PowertrainEVAP System Leak Detection Reference Orifice Low Flow
- P043FGeneric · PowertrainEVAP System Leak Detection Reference Orifice High Flow
- P0440Generic · PowertrainEVAP System
- P0441Generic · PowertrainEVAP System Incorrect Purge Flow
- P0442Generic · PowertrainEVAP System Leak Detected (small leak)
- P0443Generic · PowertrainEVAP System Purge Control Valve A Circuit
- P0444Generic · PowertrainEVAP System Purge Control Valve A Circuit Open
- P0445Generic · PowertrainEVAP System Purge Control Valve A Circuit Shorted
- P0446Generic · PowertrainEVAP System Vent Control Circuit
- P0447Generic · PowertrainEVAP System Vent Control Circuit Open
- P0448Generic · PowertrainEVAP System Vent Control Circuit Shorted
- P0449Generic · PowertrainEVAP System Vent Valve Control Circuit/Open
- P044AGeneric · PowertrainEGR Sensor C Circuit
- P044BGeneric · PowertrainEGR Sensor C Circuit Range/Performance
- P044CGeneric · PowertrainEGR Sensor C Circuit Low
- P044DGeneric · PowertrainEGR Sensor C Circuit High
- P044EGeneric · PowertrainEGR Sensor C Circuit Intermittent/Erratic
- P044FGeneric · PowertrainAIR System Switching Valve A Circuit High
- P0450Generic · PowertrainEVAP System Pressure Sensor/Switch A Circuit
- P0451Generic · PowertrainEVAP System Pressure Sensor/Switch A Circuit Range/Performance
- P0452Generic · PowertrainEVAP System Pressure Sensor/Switch A Circuit Low
- P0453Generic · PowertrainEVAP System Pressure Sensor/Switch A Circuit High
- P0454Generic · PowertrainEVAP System Pressure Sensor/Switch A Circuit Intermittent
- P0455Generic · PowertrainEVAP System Leak Detected - Large Leak
- P0456Generic · PowertrainEVAP System Leak Detected (very small leak)
- P0457Generic · PowertrainEVAP System Leak Detected (fuel cap loose/off)
- P0458Generic · PowertrainEVAP System Purge Control Valve A Circuit Low
- P0459Generic · PowertrainEVAP System Purge Control Valve A Circuit High
