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.
- P1722Lincoln · PowertrainGear 2 Incorrect Ratio
- P1722Mazda · PowertrainGear 2 Incorrect Ratio
- P1722Mercury · PowertrainGear 2 Incorrect Ratio
- P1722Other · PowertrainGear 2 Incorrect Ratio
- P1722Subaru · PowertrainAuto Trans Diagnosis Input Signal High Input
- P1723Ford · PowertrainGear 3 Incorrect Ratio
- P1723Lincoln · PowertrainGear 3 Incorrect Ratio
- P1723Mazda · PowertrainGear 3 Incorrect Ratio
- P1723Mercury · PowertrainGear 3 incorrect Ratio
- P1723Other · PowertrainGear 3 incorrect Ratio
- P1723Volkswagen · PowertrainStarter Interlock Circuit Open
- P1724Ford · PowertrainGear 4 Incorrect Ratio
- P1724Lincoln · PowertrainGear 4 Incorrect Ratio
- P1724Mazda · PowertrainGear 4 Incorrect Ratio
- P1724Mercury · PowertrainGear 4 Incorrect Ratio
- P1724Other · PowertrainGear 4 Incorrect Ratio
- P1724Volkswagen · PowertrainStarter Interlock Circuit Short To Ground
- P1725Ford · PowertrainInsufficient Engine Speed Increase During Self Test
- P1725Lincoln · PowertrainInsufficient Engine Speed Increase During Self Test
- P1725Mercury · PowertrainInsufficient Engine Speed Increase During Self Test
- P1725Other · PowertrainInsufficient Engine Speed Increase During Self Test
- P1726Ford · PowertrainInsufficient Engine Speed Decrease During Self Test
- P1726Jaguar · PowertrainEngine Overspeed
- P1726Lincoln · PowertrainInsufficient Engine Speed Decrease During Self Test
- P1726Mercury · PowertrainInsufficient Engine Speed Decrease During Self Test
- P1726Other · PowertrainInsufficient Engine Speed Decrease During Self Test
- P1726Volkswagen · PowertrainWheel Speed Signal 4 Range Performance
- P1727Ford · PowertrainCoast Clutch Solenoid Inductive Signature Malfunction
- P1727Lincoln · PowertrainCoast Clutch Solenoid Inductive Signature Malfunction
- P1727Mercury · PowertrainCoast Clutch Solenoid Inductive Signature Malfunction
