What does code P289A mean?

Q: What does code P289A mean?

Cylinder 3 Ion Current Sense Circuit Low. P289A indicates that the engine control module has detected an abnormally low voltage or current on the ion current sense circuit for cylinder 3, which is used to monitor combustion quality and detect misfires. The circuit typically consists of a sensor or electrode in the cylinder and a signal wire to the module, and a low reading means the module is seeing less signal than expected during the ion current measurement window.

DTC codes / P28xx · Transmission / P289A

P289ACylinder 3 Ion Current Sense Circuit Low

P289A indicates that the engine control module has detected an abnormally low voltage or current on the ion current sense circuit for cylinder 3, which is used to monitor combustion quality and detect misfires. The circuit typically consists of a sensor or electrode in the cylinder and a signal wire to the module, and a low reading means the module is seeing less signal than expected during the ion current measurement window.

SystemPowertrain

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyIntermediate

AreaTransmission

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