What does code P28AA mean?

Q: What does code P28AA mean?

Cylinder 7 Ion Current Sense Circuit Low. P28AA indicates that the engine control module has detected an abnormally low voltage on the ion current sense circuit for cylinder 7, which is used to monitor combustion quality and detect misfires. The ion current sensing system applies a small voltage across the spark plug gap after the spark event and measures the resulting current to assess cylinder pressure and combustion consistency.

DTC codes / P28xx · Transmission / P28AA

P28AACylinder 7 Ion Current Sense Circuit Low

P28AA indicates that the engine control module has detected an abnormally low voltage on the ion current sense circuit for cylinder 7, which is used to monitor combustion quality and detect misfires. The ion current sensing system applies a small voltage across the spark plug gap after the spark event and measures the resulting current to assess cylinder pressure and combustion consistency.

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.