Generic fault codes
9415 Generic OBD-II fault codes: what each one means, 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.
- P040CGeneric · PowertrainEGR Temperature Sensor A Circuit Low
- P040DGeneric · PowertrainEGR Temperature Sensor A Circuit High
- P040EGeneric · PowertrainEGR Temperature Sensor A Circuit Intermittent/Erratic
- P040FGeneric · PowertrainEGR Temperature Sensor A/B Correlation
- P0410Generic · PowertrainAIR System A
- P0411Generic · PowertrainAIR System A Incorrect Flow Detected
- P0412Generic · PowertrainAIR System Switching Valve A Circuit
- P0413Generic · PowertrainAIR System Switching Valve A Circuit Open
- P0414Generic · PowertrainAIR System Switching Valve A Circuit Shorted
- P0415Generic · PowertrainAIR System Switching Valve B Circuit
- P0416Generic · PowertrainAIR System Switching Valve B Circuit Open
- P0417Generic · PowertrainAIR System Switching Valve B Circuit Shorted
- P0418Generic · PowertrainAIR System Control A Circuit
- P0419Generic · PowertrainAIR System Control B Circuit
- P041AGeneric · PowertrainEGR Temperature Sensor B Circuit
- P041BGeneric · PowertrainEGR Temperature Sensor B Circuit Range/Performance
- P041CGeneric · PowertrainEGR Temperature Sensor B Circuit Low
- P041DGeneric · PowertrainEGR Temperature Sensor B Circuit High
- P041EGeneric · PowertrainEGR Temperature Sensor B Circuit Intermittent/Erratic
- P041FGeneric · PowertrainAIR System Switching Valve A Circuit Low
- P0420Generic · PowertrainCatalyst System Efficiency Below Threshold Bank 1
- P0421Generic · PowertrainCatalyst 1 Efficiency Below Threshold Bank 1
- P0422Generic · PowertrainCatalyst 2 Efficiency Below Threshold Bank 1
- P0423Generic · PowertrainHeated Catalyst Efficiency Below Threshold Bank 1
- P0424Generic · PowertrainHeated Catalyst Temperature Below Threshold Bank 1
- P0425Generic · PowertrainCatalyst Temperature Sensor Circuit Bank 1 Sensor 1
- P0426Generic · PowertrainCatalyst Temperature Sensor Circuit Range/Performance Bank 1 Sensor 1
- P0427Generic · PowertrainCatalyst Temperature Sensor Circuit Low Bank 1 Sensor 1
- P0428Generic · PowertrainCatalyst Temperature Sensor Circuit High Bank 1 Sensor 1
- P0429Generic · PowertrainCatalyst Heater Control Circuit/Open Bank 1
