Powertrain
generic / SAE
P04CB
Fuel Fill Door Open Request Sensor or Switch Circuit High
Same as P04C8 with the signal voltage shorted to supply or constantly high. Wiring faults of this kind typically come from chafing, water ingress at connector seals, or pin push-back — a wiggle test on the harness while the code is active often confirms the location.
SystemPowertrain
Typegeneric / SAE
GroupP0
Range / number4 / CB
Possible causes
- Signal shorted to supply high
- Connector pins corroded - high contact resistance low
- Supply wire pinched against B+ source low
Inspection / repair
- Difficulty: easy
- DIY: possible
- Estimated cost: 60–220 €
- Estimated time: 0.4–1 h
- Component: fuel fill door request switch
Sources
References
sae:J2012