What does code P04B8 mean?

Q: What does code P04B8 mean?

Fuel Fill Door Position Sensor/Switch Circuit. P04B8 indicates that the powertrain control module (PCM) has detected an abnormal signal from the fuel fill door position sensor or switch circuit, which monitors whether the fuel door is open or closed. The computer expects a specific voltage or state change when the door is opened or closed, and it sets this code when the signal stays out of range or does not change as expected.

DTC codes / P04xx · Auxiliary emission controls / P04B8

P04B8Fuel Fill Door Position Sensor/Switch Circuit

P04B8 indicates that the powertrain control module (PCM) has detected an abnormal signal from the fuel fill door position sensor or switch circuit, which monitors whether the fuel door is open or closed. The computer expects a specific voltage or state change when the door is opened or closed, and it sets this code when the signal stays out of range or does not change as expected.

SystemPowertrain

Code typeGeneric (all makes)

SeverityLow

Fix difficultyIntermediate

AreaAuxiliary emission controls

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