P04B9

Fuel Fill Door Position Sensor/Switch Circuit Low

Severity

✅ Low

Can you drive?

Yes, but get it checked soon

Approx. repair cost

$22–89 (est.)

Symptoms

Check Engine Light Is On
EVAP system malfunction
Possible problems with fuel refueling

Causes

Sensor circuit open
Short circuit to ground
Faulty cover position sensor
Damaged wiring harness
Bad contacts in connectors

How to Fix

Visually check the fuel tank cap and its mechanism
Check the integrity of the wiring harness to the sensor
Measure the resistance of the sensor in different positions
Check the voltage and ground in the sensor circuit
If necessary, replace the sensor or repair the wiring harness

Related codes

P0442 P0455 P0456