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.
- P1815GMC · PowertrainTransmission Range Switch Start In Wrong Range
- P1815Lincoln · PowertrainTransmission 4-Wheel Drive Mode Select Short Circuit To Ground
- P1815Mercury · PowertrainTransmission 4-Wheel Drive Mode Select Short Circuit To Ground
- P1815Oldsmobile · PowertrainTransmission Range Switch Start In Wrong Range
- P1815Other · PowertrainTransmission 4-Wheel Drive Mode Select Short Circuit To Ground
- P1815Saturn · PowertrainTransmission Range Switch Start In Wrong Range
- P1815Volkswagen · PowertrainPressure Control Solenoid 1 Short To B+
- P1816Buick · PowertrainTFP Valve Position Switch Park/Neutral With Drive Ratio
- P1816Cadillac · PowertrainTFP Valve Position Switch Park/Neutral With Drive Ratio
- P1816Chevrolet · PowertrainTFP Valve Position Switch Park/Neutral With Drive Ratio
- P1816GM · PowertrainTFP Valve Position Switch Park Neutral With Drive Ratio
- P1816GMC · PowertrainTFP Valve Position Switch Park Neutral With Drive Ratio
- P1816Oldsmobile · PowertrainTFP Valve Position Switch Park Neutral With Drive Ratio
- P1816Other · PowertrainTransmission Neutral Safety Switch Circuit Failure
- P1816Saturn · PowertrainTFP Valve Position Switch Park Neutral With Drive Ratio
- P1817Buick · PowertrainTFP Valve Position Switch Reverse With Drive Ratio
- P1817Cadillac · PowertrainTFP Valve Position Switch Reverse With Drive Ratio
- P1817Chevrolet · PowertrainTFP Valve Position Switch Reverse With Drive Ratio
- P1817GM · PowertrainTFP Valve Position Switch Reverse With Drive Ratio
- P1817GMC · PowertrainTFP Valve Position Switch Reverse With Drive Ratio
- P1817Oldsmobile · PowertrainTFP Valve Position Switch Reverse With Drive Ratio
- P1817Other · PowertrainTransmission Neutral Safety Switch Open Circuit
- P1817Saturn · PowertrainTFP Valve Position Switch Reverse With Drive Ratio
- P1818Buick · PowertrainTFP Valve Position Switch Drive Without Drive Ratio
- P1818Cadillac · PowertrainTFP Valve Position Switch Drive Without Drive Ratio
- P1818Chevrolet · PowertrainTFP Valve Position Switch Drive Without Drive Ratio
- P1818GM · PowertrainTFP Valve Position Switch Drive Without Drive Ratio
- P1818GMC · PowertrainTFP Valve Position Switch Drive Without Drive Ratio
- P1818Oldsmobile · PowertrainTFP Valve Position Switch Drive Without Drive Ratio
- P1818Other · PowertrainTransmission Neutral Safety Switch Short Circuit To Battery
