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.
- P2BA8Generic · PowertrainNOx Exceedence - Interruption of Reagent Dosing Activity
- P2BA8Audi · PowertrainFaulty NOx Sensors, NOx Sensors harness is open or shorted, NOx Sensors circuit poor electrical connection, Faulty Diesel Particulate Filter (DPF)
- P2BA9Generic · PowertrainNOx Exceedence - Insufficient Reagent Quality
- P2BAAGeneric · PowertrainNOx Exceedence - Low Reagent Consumption
- P2BABGeneric · PowertrainNOx Exceedence - Incorrect EGR Flow
- P2BACGeneric · PowertrainNOx Exceedence - Deactivation of EGR
- P2BADGeneric · PowertrainNOx Exceedence - Root Cause Unknown
- P2BAEGeneric · PowertrainNOx Exceedence - NOx control monitoring system
- P2BAFGeneric · PowertrainNOx System Driver Inducement Active
- P2BB0Generic · PowertrainAlternative Fuel Consumption Too Low
- P2BB1Generic · PowertrainAlternative Fuel Consumption Too High
- P2BB2Generic · PowertrainAlternative Fuel Tank Empty
- P2BB3Generic · PowertrainFuel Pump Secondary Circuit Performance
- P2BB4Generic · PowertrainEngine Coolant Temperature Sensor 4 Circuit Intermittent/Erratic
- P2BB5Generic · PowertrainEngine Coolant Temperature Sensor 5 Circuit Intermittent/Erratic
- P2BB6Generic · PowertrainEngine Coolant Temperature Sensor 6 Circuit
- P2BB7Generic · PowertrainEngine Coolant Temperature Sensor 6 Circuit Range/Performance
- P2BB8Generic · PowertrainEngine Coolant Temperature Sensor 6 Circuit Low
- P2BB9Generic · PowertrainEngine Coolant Temperature Sensor 6 Circuit High
- P2BBAGeneric · PowertrainEngine Coolant Temperature Sensor 6 Circuit Intermittent/Erratic
- P2BBBGeneric · PowertrainTurbocharger/Supercharger Bypass Valve A Position Sensor Circuit
- P2BBCGeneric · PowertrainTurbocharger/Supercharger Bypass Valve A Position Sensor Circuit Low
- P2BBDGeneric · PowertrainTurbocharger/Supercharger Bypass Valve A Position Sensor Circuit High
- P2BBEGeneric · PowertrainTurbocharger/Supercharger Bypass Valve A Position Exceeded Learning Limit
- P2BBFGeneric · PowertrainTurbocharger/Supercharger Bypass Valve A Supply Voltage Low
- P2BC0Generic · PowertrainTurbocharger/Supercharger Bypass Valve A Driver Current/Temperature Too High
- P2BC1Generic · PowertrainCharge Air Cooler Coolant Pump A Stuck/Stalled
- P2BC2Generic · PowertrainCharge Air Cooler Coolant Pump A Supply Voltage Circuit
- P2BC3Generic · PowertrainCharge Air Cooler Coolant Pump A Control Module Overtemperature
- P2BC4Generic · PowertrainBattery Charging System Positive Contactor B Circuit
