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.
- P1390GM · PowertrainWheel Speed Sensor 1 G-Sensor Circuit
- P1390GMC · PowertrainWheel Speed Sensor 1 G-Sensor Circuit
- P1390Jeep · PowertrainTiming Belt Skipped One Tooth Or More
- P1390Lincoln · PowertrainOctane Adjust Out of Self-Test Range
- P1390Mazda · PowertrainOctane Adjust Shorting Bar Out Or Circuit Open
- P1390Mercury · PowertrainOctane Adjust Out of Self-Test Range
- P1390Mitsubishi · PowertrainTiming Belt Skipped One Tooth Or More
- P1390Oldsmobile · PowertrainWheel Speed Sensor 1 G-Sensor Circuit
- P1390Other · PowertrainOctane Adjust Pin Out Of Self Test Range
- P1390Plymouth · PowertrainTiming Belt Skipped One Tooth Or More
- P1390Pontiac · PowertrainTiming Belt Skipped One Tooth Or More
- P1390Saturn · PowertrainWheel Speed Sensor 1 G-Sensor Circuit
- P1391Generic · PowertrainGlow Plug Circuit Low Input (Bank #1)
- P1391Buick · PowertrainWheel Speed Sensor 1, G-Sensor Circuit Performance
- P1391Cadillac · PowertrainWheel Speed Sensor 1, G-Sensor Circuit Performance
- P1391Chevrolet · PowertrainWheel Speed Sensor 1, G-Sensor Circuit Performance
- P1391Chrysler · PowertrainWheel Speed Sensor 1, G-Sensor Circuit Performance
- P1391Dodge · PowertrainIntermittent Loss of CMP Or CKP
- P1391Ford · PowertrainGlow Plug Circuit Low Input Bank 1
- P1391GM · PowertrainWheel Speed Sensor 1 G-Sensor Circuit Performance
- P1391GMC · PowertrainWheel Speed Sensor 1 G-Sensor Circuit Performance
- P1391Jeep · PowertrainIntermittent Loss of CMP Or CKP
- P1391Lincoln · PowertrainGlow Plug Circuit Low Input Bank 1
- P1391Mercury · PowertrainGlow Plug Circuit Low Input Bank 1
- P1391Mitsubishi · PowertrainIntermittent Loss Of CMP Or CKP Sensor Signals
- P1391Oldsmobile · PowertrainWheel Speed Sensor 1 G-Sensor Circuit Performance
- P1391Other · PowertrainGlow Plug Circuit Low Input (Bank #1)
- P1391Plymouth · PowertrainIntermittent Loss of CMP Or CKP
- P1391Pontiac · PowertrainIntermittent Loss of CMP Or CKP
- P1391Saturn · PowertrainWheel Speed Sensor 1 G-Sensor Circuit Performance
