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.
- U0308Generic · NetworkSoftware Incompatibility With Throttle Actuator Control Module
- U0309Generic · NetworkSoftware Incompatibility With Alternative Fuel Control Module
- U030AGeneric · NetworkSoftware Incompatibility With Evaporative Emission System Leak Detection Control Module
- U030BGeneric · NetworkSoftware Incompatibility With Glow Plug Control Module 2
- U030CGeneric · NetworkSoftware Incompatibility With Reductant Quality Module
- U030DGeneric · NetworkSoftware Incompatibility With NOx Sensor A
- U030EGeneric · NetworkSoftware Incompatibility With NOx Sensor B
- U030FGeneric · NetworkSoftware Incompatibility With Reductant Control Module
- U0310Generic · NetworkSoftware Incompatibility With Fuel Pump Control Module
- U0311Generic · NetworkSoftware Incompatibility With Drive Motor Control Module
- U0312Generic · NetworkSoftware Incompatibility With Battery Energy Control Module A
- U0313Generic · NetworkSoftware Incompatibility With Battery Energy Control Module B
- U0314Generic · NetworkSoftware Incompatibility With Four-Wheel Drive Clutch Control Module
- U0315Generic · NetworkSoftware Incompatibility With Anti-Lock Brake System (ABS) Control Module
- U0316Generic · NetworkSoftware Incompatibility With Vehicle Dynamics Control Module
- U0317Generic · NetworkSoftware Incompatibility With Park Brake Control Module
- U0318Generic · NetworkSoftware Incompatibility With Brake System Control Module A
- U0319Generic · NetworkSoftware Incompatibility With Steering Effort Control Module
- U031AGeneric · NetworkSoftware Incompatibility With Transmission Range Control Module
- U031BGeneric · NetworkSoftware Incompatibility With DC/DC Converter Control Module A
- U031CGeneric · NetworkSoftware Incompatibility With Brake System Control Module B
- U031DGeneric · NetworkSoftware Incompatibility With Parking Assist Control Module A
- U031EGeneric · NetworkSoftware Incompatibility With Parking Assist Control Module B
- U031FGeneric · NetworkSoftware Incompatibility With Accessory Protocol Interface Module
- U0320Generic · NetworkSoftware Incompatibility With Power Steering Control Module
- U0321Generic · NetworkSoftware Incompatibility With Suspension Control Module A
- U0322Generic · NetworkSoftware Incompatibility With Body Control Module
- U0323Generic · NetworkSoftware Incompatibility With Instrument Panel Control Module
- U0324Generic · NetworkSoftware Incompatibility With HVAC Control Module
- U0325Generic · NetworkSoftware Incompatibility With Auxiliary Heater Control Module