What does code P2277 mean?

Q: What does code P2277 mean?

O2 Sensor Signal Stuck Rich (Bank 2 Sensor 3). P2277 means the powertrain control module (PCM) has detected that the downstream oxygen sensor on bank 2, sensor 3, is reporting a rich exhaust condition and the signal is stuck there instead of switching normally. The PCM monitors this sensor's voltage over time and flags the code when the reading remains high, indicating a persistently rich mixture or a sensor that can no longer respond to changing conditions.

DTC codes / P22xx · Fuel and air metering (injector circuits) / P2277

P2277O2 Sensor Signal Stuck Rich (Bank 2 Sensor 3)

P2277 means the powertrain control module (PCM) has detected that the downstream oxygen sensor on bank 2, sensor 3, is reporting a rich exhaust condition and the signal is stuck there instead of switching normally. The PCM monitors this sensor's voltage over time and flags the code when the reading remains high, indicating a persistently rich mixture or a sensor that can no longer respond to changing conditions.

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.