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.
- P1620Buick · PowertrainLow Coolant Circuit
- P1620Cadillac · PowertrainLow Coolant Circuit
- P1620Chevrolet · PowertrainLow Coolant Circuit
- P1620GM · PowertrainLow Coolant Circuit
- P1620GMC · PowertrainLow Coolant Circuit
- P1620Oldsmobile · PowertrainLow Coolant Circuit
- P1620Other · PowertrainSBDS Interactive Codes
- P1620Saturn · PowertrainLow Coolant Circuit
- P1620Volkswagen · PowertrainEngine Coolant Temperature Signal Open Short To B+
- P1621Buick · PowertrainPCM Memory Performance
- P1621Cadillac · PowertrainPCM Memory Performance
- P1621Chevrolet · PowertrainPCM Memory Performance
- P1621GM · PowertrainPCM Memory Performance
- P1621GMC · PowertrainPCM Memory Performance
- P1621Mazda · PowertrainImmobilizer System Fault
- P1621Oldsmobile · PowertrainPCM Memory Performance
- P1621Other · PowertrainControl Module Long Term Memory Performance/ Immobilizer Code Words Do Not Match
- P1621Saturn · PowertrainPCM Memory Performance
- P1621Volkswagen · PowertrainEngine Coolant Temperature Signal Short To Ground
- P1622BMW · PowertrainMAP Cooling Control Circuit Electrical
- P1622Buick · PowertrainCylinder Select
- P1622Cadillac · PowertrainCylinder Select
- P1622Chevrolet · PowertrainCylinder Select
- P1622GM · PowertrainCylinder Select
- P1622GMC · PowertrainCylinder Select
- P1622Mazda · PowertrainImmobilizer System Fault
- P1622Mercedes-Benz · PowertrainElectrohydraulic Shut-Off Actuator Y11
- P1622Oldsmobile · PowertrainCylinder Select
- P1622Other · PowertrainImmobilizer ID Does Not Match
- P1622Saturn · PowertrainCylinder Select
