What does code P03AC mean?

Q: What does code P03AC mean?

Cylinder 3 Pressure Sensor Circuit High. P03AC indicates that the powertrain control module (PCM) has detected an abnormally high voltage on the signal circuit of the cylinder 3 pressure sensor, which is used to monitor combustion pressure for that specific cylinder. The PCM expects the sensor's output to stay within a calibrated range, and a sustained high voltage tells the module that the circuit is shorted to voltage or the sensor has failed internally.

DTC codes / P03xx · Ignition system and misfire / P03AC

P03ACCylinder 3 Pressure Sensor Circuit High

P03AC indicates that the powertrain control module (PCM) has detected an abnormally high voltage on the signal circuit of the cylinder 3 pressure sensor, which is used to monitor combustion pressure for that specific cylinder. The PCM expects the sensor's output to stay within a calibrated range, and a sustained high voltage tells the module that the circuit is shorted to voltage or the sensor has failed internally.

SystemPowertrain

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyIntermediate

AreaIgnition system and misfire

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