Powertrain fault codes
14821 Powertrain 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.
- 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
- P0440Audi · PowertrainMissing fuel cap, Defective or damaged fuel cap, Distorted or damaged Fuel Tank Filler Neck, Torn or punctured Evaporative system hose(s), Defective Fuel Tank Sending Unit gasket or seal, Split or damaged Carbon Canister, Defective Evaporative Vent Valve and or Evaporative Purge Valve, Defective or damaged fuel tank
- P0441Generic · PowertrainEVAP System Incorrect Purge Flow
- P0441Audi · PowertrainMissing fuel cap, Stuck open or closed purge valve, Defective or damaged fuel cap, Distorted damaged or cracked Fuel Tank Filler Neck, Torn or punctured Evaporative system hose(s), Defective Fuel Tank Sending Unit gasket or seal, Split or damaged Carbon Canister, Defective Evaporative Vent Valve, Defective or damaged fuel tank
- P0442Generic · PowertrainEVAP System Leak Detected (small leak)
- P0442Audi · PowertrainDefective or damaged fuel cap, Distorted or damaged Fuel Tank Filler Neck, Small tear or puncture in the Evaporative system hose(s) and or Carbon Canister, Defective Fuel Tank Sending Unit gasket or seal, Small split in a seam of the Carbon Canister, Defective Evaporative Vent Valve and or Evaporative Purge Valve, Defective or damaged Fuel Tank, Defective Fuel Tank Pressure Sensor, Defective Leak Detection Pump, Slightly loose and or worn clamps or hardened O-rings anywhere in the EVAP system
- P0442Dodge · PowertrainMedium EVAP 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
- P0455Audi · PowertrainMissing fuel cap, Defective or damaged fuel cap, Distorted or damaged Fuel Tank Filler Neck, Torn or punctured Evaporative system hose(s), Defective Fuel Tank Sending Unit gasket or seal, Split or damaged Carbon Canister, Defective Evaporative Vent Valve and or Evaporative Purge Valve, Defective or damaged fuel tank, Defective Fuel Tank Pressure Sensor
