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.
- P2491Generic · PowertrainEGR Cooler Bypass Control Circuit High Bank 2
- P2492Generic · PowertrainEGR Cooler Bypass Position Sensor Circuit Bank 1
- P2493Generic · PowertrainEGR Cooler Bypass Position Sensor Range/Performance Bank 1
- P2494Generic · PowertrainEGR Cooler Bypass Position Sensor Circuit Low Bank 1
- P2495Generic · PowertrainEGR Cooler Bypass Position Sensor Circuit High Bank 1
- P2496Generic · PowertrainEGR Cooler Bypass Position Sensor Circuit Intermittent/Erratic Bank 1
- P2497Generic · PowertrainEGR Cooler Bypass Position Sensor Circuit Bank 2
- P2498Generic · PowertrainEGR Cooler Bypass Position Sensor Range/Performance Bank 2
- P2499Generic · PowertrainEGR Cooler Bypass Position Sensor Circuit Low Bank 2
- P249AGeneric · PowertrainEGR Cooler Bypass Position Sensor Circuit High Bank 2
- P249BGeneric · PowertrainEGR Cooler Bypass Position Sensor Circuit Intermittent/Erratic Bank 2
- P249CGeneric · PowertrainExcessive Time To Enter Closed Loop Reductant Injection Control
- P249DGeneric · PowertrainClosed Loop Reductant Injection Control At Limit - Flow Too Low
- P249EGeneric · PowertrainClosed Loop Reductant Injection Control At Limit - Flow Too High
- P249FGeneric · PowertrainExcessive Time To Enter Closed Loop Particulate Filter Regeneration Control
- P24A0Generic · PowertrainClosed Loop Particulate Filter Regeneration Control At Limit - Temperature Too Low
- P24A1Generic · PowertrainClosed Loop Particulate Filter Regeneration Control At Limit - Temperature Too High
- P24A2Generic · PowertrainParticulate Filter Regeneration Incomplete Bank 1
- P24A3Generic · PowertrainParticulate Filter Restriction - Soot Accumulation Bank 2
- P24A4Generic · PowertrainParticulate Filter Restriction - Soot Accumulation Too High Bank 1
- P24A5Generic · PowertrainEGR Cooler Bypass Control Stuck/Open Bank 1
- P24A6Generic · PowertrainEGR Cooler Bypass Control Stuck/Open Bank 2
- P24A7Generic · PowertrainEGR Cooler Coolant Pump Control Circuit/Open
- P24A8Generic · PowertrainEGR Cooler Coolant Pump Performance/Stuck Off
- P24A9Generic · PowertrainEGR Cooler Coolant Pump Control Circuit Low
- P24AAGeneric · PowertrainEGR Cooler Coolant Pump Control Circuit High
- P24ABGeneric · PowertrainEGR Cooler Coolant Pump Stuck On
- P24ACGeneric · PowertrainEGR Cooler Coolant Pump Feedback Circuit Low
- P24ADGeneric · PowertrainEGR Cooler Coolant Pump Feedback Circuit High
- P24AEGeneric · PowertrainParticulate Matter Sensor Circuit