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.
- P1788Mazda · PowertrainPressure Control Solenoid B Circuit Open
- P1788Mercury · PowertrainPressure Control Solenoid B Open Circuit
- P1788Nissan · PowertrainPressure Control Solenoid B Circuit Open
- P1788Other · PowertrainPressure Control Solenoid "B" Open Circuit
- P1788Volkswagen · PowertrainReversing Light Circuit Short To B+
- P1789Ford · PowertrainPressure Control Solenoid B Short Circuit
- P1789Jaguar · PowertrainIgnition Supply Malfunction
- P1789Lincoln · PowertrainPressure Control Solenoid B Short Circuit
- P1789Mazda · PowertrainPressure Control Solenoid B Circuit Shorted
- P1789Mercury · PowertrainPressure Control Solenoid B Short Circuit
- P1789Nissan · PowertrainPressure Control Solenoid B Circuit Shorted
- P1789Other · PowertrainPressure Control Solenoid "B" Short Circuit
- P1789Volkswagen · PowertrainIdle Speed Intervention Circuit Error Message From Engine Control
- P1790Acura · PowertrainTCM A/T TP Sensor Circuit Fault
- P1790Buick · PowertrainTransmission Control Module Checksum
- P1790Cadillac · PowertrainTransmission Control Module Checksum
- P1790Chevrolet · PowertrainTransmission Control Module Checksum
- P1790GM · PowertrainTransmission Control Module Checksum
- P1790GMC · PowertrainTransmission Control Module Checksum
- P1790Honda · PowertrainTCM A/T TP Sensor Circuit Fault
- P1790Infiniti · PowertrainTCM A/T TP Sensor Circuit Fault
- P1790Jaguar · PowertrainIgnition Supply Malfunction
- P1790Mazda · PowertrainTP Mechanical Circuit
- P1790Nissan · PowertrainTP Mechanical Circuit
- P1790Oldsmobile · PowertrainTransmission Control Module Checksum
- P1790Other · PowertrainTP (Mechanical) Circuit Malfunction
- P1790Saturn · PowertrainTransmission Control Module Checksum
- P1790Volkswagen · PowertrainTransmission Range Display Circuit Open
- P1791Acura · PowertrainTCM A/T Vehicle Speed Sensor Circuit Fault
- P1791Buick · PowertrainTransmission Control Module Loop
