Audi DTC P1255 – Engine Coolant Temperature Circuit Short to Ground
DTC P1255 meaning on Audi
DTC P1255 on an Audi indicates an issue with the Engine Coolant Temperature (ECT) circuit being shorted to ground. The Engine Control Module (ECM) monitors the ECT sensor to ensure the engine is operating at the correct temperature. A short to ground in this circuit can lead to inaccurate temperature readings and affect engine performance.
Audi DTC P1255 symptoms
Symptoms of DTC P1255 on an Audi may include:
- Check Engine Light illuminated
- Inaccurate temperature gauge readings
- Engine overheating or running too cold
- Poor fuel economy
- Engine misfires or rough idling
Audi DTC P1255 causes
Common causes of DTC P1255 on an Audi include:
- Short circuit in the ECT sensor wiring
- Faulty ECT sensor
- Corrosion or damage to the ECT sensor connector
- ECM malfunction
Audi DTC P1255 seriousness
DTC P1255 should not be ignored as it can lead to engine performance issues and potential damage if the engine is allowed to overheat or run too cold. It is recommended to address this issue promptly to prevent further complications.
How to diagnose DTC P1255 on Audi
To diagnose DTC P1255 on an Audi, a mechanic would typically perform the following steps:
- Use a diagnostic scanner to retrieve the fault code and freeze frame data
- Inspect the ECT sensor wiring for any signs of damage or short circuits
- Test the ECT sensor using a multimeter to check for proper resistance values
- Check the ECT sensor connector for corrosion or loose connections
- If necessary, perform a continuity test on the wiring harness to identify any shorts to ground
How to fix DTC P1255 on Audi
To fix DTC P1255 on an Audi, the following steps may be taken:
- Repair any damaged wiring or connectors in the ECT circuit
- Replace the ECT sensor if it is found to be faulty
- If the ECM is determined to be the issue, it may need to be reprogrammed or replaced
- Clear the fault code and test drive the vehicle to ensure the issue has been resolved
How to erase DTC P1255 on Audi
To erase DTC P1255 on an Audi, follow these steps:
- Use a diagnostic scanner to clear the fault code from the ECM memory
- After clearing the code, start the engine and ensure the Check Engine Light is no longer illuminated
- Perform a test drive to verify that the issue has been resolved
Recommended tools for Audi diagnostics
Explore our expert picks: The Best OBD2 Scanners for 2025
Easy-to-use Multimeter for reliable diagnostics: AstroAI Auto-ranging Multimeter
Some of the links on this page may be affiliate links, which means we may earn a small commission if you make a purchase. This helps us keep our DTC database up to date and provide valuable content for free. We only recommend products that we have tested and believe to be the best in their class.