What does code P22C4 mean?

DTC codes / P22xx · Fuel and air metering (injector circuits) / P22C4

P22C4O2 Sensor Pumping Current Trim Circuit High (Bank 2 Sensor 2)

P22C4 indicates that the engine control module has detected an abnormally high current in the pumping current trim circuit for the downstream oxygen sensor on bank 2. This sensor, often a wideband air-fuel ratio sensor, uses a pump cell to maintain a reference air-fuel ratio, and the trim circuit adjusts the pump current to keep the sensor's output accurate. The code sets when the measured pumping current exceeds the expected range, signaling a circuit fault or sensor degradation.

SystemPowertrain

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyIntermediate

AreaFuel and air metering (injector circuits)

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