What does code P1255 mean?

Q: What does code P1255 mean?

Engine Coolant Temperature Circuit Short To Ground. P1255 on a Volkswagen means the engine control module (ECM) has detected a short to ground on the engine coolant temperature (ECT) sensor signal circuit. The ECM expects a voltage between roughly 0.5 and 4.5 volts as coolant temperature changes, and a near-zero voltage reading tells it the signal wire is touching ground or the sensor has failed internally.

DTC codes / Volkswagen codes / P1255

P1255 · VolkswagenEngine Coolant Temperature Circuit Short To Ground

P1255 on a Volkswagen means the engine control module (ECM) has detected a short to ground on the engine coolant temperature (ECT) sensor signal circuit. The ECM expects a voltage between roughly 0.5 and 4.5 volts as coolant temperature changes, and a near-zero voltage reading tells it the signal wire is touching ground or the sensor has failed internally.

SystemPowertrain

Code typeVolkswagen specific

SeverityMedium

Fix difficultyIntermediate

AreaFuel and air metering (injector circuits)

Guidance is general and written for Volkswagen vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.