What does code P28B0 mean?

Q: What does code P28B0 mean?

Cylinder 9 Ion Current Sense Circuit. P28B0 indicates that the engine control module has detected an abnormal signal from the ion current sense circuit for cylinder 9, which is used to monitor combustion quality and detect misfire. The circuit typically measures ionization current across the spark plug gap after ignition, and this code sets when the voltage or current reading falls outside the expected range for that cylinder.

DTC codes / P28xx · Transmission / P28B0

P28B0Cylinder 9 Ion Current Sense Circuit

P28B0 indicates that the engine control module has detected an abnormal signal from the ion current sense circuit for cylinder 9, which is used to monitor combustion quality and detect misfire. The circuit typically measures ionization current across the spark plug gap after ignition, and this code sets when the voltage or current reading falls outside the expected range for that cylinder.

SystemPowertrain

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyProfessional

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.