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.
- P1320Oldsmobile · PowertrainIC Module 4X Ref Circuit Intermittent No Pulses
- P1320Saturn · PowertrainIC Module 4X Ref Circuit Intermittent No Pulses
- P1320Volkswagen · PowertrainKnock Sensor 2 Circuit Short To Ground
- P1321Buick · PowertrainElectronic Ignition System Fault Line
- P1321Cadillac · PowertrainElectronic Ignition System Fault Line
- P1321Chevrolet · PowertrainElectronic Ignition System Fault Line
- P1321Chrysler · PowertrainElectronic Ignition System Fault Line
- P1321GM · PowertrainElectronic Ignition System Fault Line
- P1321GMC · PowertrainElectronic Ignition System Fault Line
- P1321Oldsmobile · PowertrainElectronic Ignition System Fault Line
- P1321Saturn · PowertrainElectronic Ignition System Fault Line
- P1321Volkswagen · PowertrainKnock Sensor 3 Circuit Low Input
- P1322Buick · PowertrainEI System Or Ignition Control Missing
- P1322Cadillac · PowertrainEI System Or Ignition Control Missing
- P1322Chevrolet · PowertrainEI System Or Ignition Control Missing
- P1322Chrysler · PowertrainEI System Or Ignition Control Missing
- P1322GM · PowertrainEI System Or Ignition Control Missing
- P1322GMC · PowertrainEI System Or Ignition Control Missing
- P1322Oldsmobile · PowertrainEI System Or Ignition Control Missing
- P1322Saturn · PowertrainEI System Or Ignition Control Missing
- P1322Volkswagen · PowertrainKnock Sensor 3 Circuit High Input
- P1323Buick · Powertrain24X Reference Circuit Low Frequency
- P1323Cadillac · Powertrain24X Reference Circuit Low Frequency
- P1323Chevrolet · Powertrain24X Reference Circuit Low Frequency
- P1323Chrysler · Powertrain24X Reference Circuit Low Frequency
- P1323GM · Powertrain24X Reference Circuit Low Frequency
- P1323GMC · Powertrain24X Reference Circuit Low Frequency
- P1323Oldsmobile · Powertrain24X Reference Circuit Low Frequency
- P1323Saturn · Powertrain24X Reference Circuit Low Frequency
- P1323Volkswagen · PowertrainKnock Sensor 4 Circuit Low Input
