Tool
Fault code lookup
410 generic OBD-II codes explained for mechanics: what the code means, the symptoms, common causes, what to check first and whether the car can be driven. Each code links to real repair cases and help requests.
Most looked-up codes
How to read a fault code
P
Powertrain: engine, fuel, emissions, transmission
Powertrain: engine, fuel, emissions, transmission
U
Network: communication between modules
Network: communication between modules
B · C
Body and chassis (mostly manufacturer-specific)
Body and chassis (mostly manufacturer-specific)
P0 · P2
Generic codes: same meaning on every car
Generic codes: same meaning on every car
P1 · P3
Manufacturer-specific: check the service data
Manufacturer-specific: check the service data
The digits after the letter narrow it down: for example P01xx and P02xx are fuel and air metering, P03xx ignition and misfires, P04xx emissions controls, P05xx speed and idle, P06xx the control module and outputs, P07xx the transmission. A code tells you which circuit or system failed a self-test, not which part to replace: always confirm with a measurement.
Codes by system
- Emissions: 103 codes
- Fuel: 64 codes
- Air intake: 50 codes
- Transmission: 47 codes
- Electrical: 42 codes
- Sensors: 33 codes
- Ignition: 24 codes
- Engine mechanical: 22 codes
- Starting: 18 codes
- Cooling: 7 codes