Fault Family System: Powertrain (P-Codes) 26 SAE Codes

Fuel Fill Door Actuator Circuit

Diagnostic & Technical Explanation

Code P04B5 (Fuel Fill Door Stuck Open) covers the electrically actuated, capless fuel fill door system: its position sensor/switch, lock/unlock control circuits, and open-request switch. It sets when the ECM/body module detects an open, shorted, out-of-range, or stuck-open/stuck-closed condition anywhere in that system. Causes are a failed door actuator motor, a corroded or misaligned position switch, a mechanically jammed door (ice, collision damage, debris), or damaged wiring in the fender-mounted harness.

These 26 diagnostic trouble codes share one detection mechanism and one repair path, which is why MechanicDB groups them into a single authored fault family rather than repeating the same explanation 26 times.

Codes in this family (26)

Code	Definition	Repair coverage
P04B5	Fuel Fill Door Stuck Open	4 ranked fixes
P04B6	Fuel Fill Door Stuck Closed	4 ranked fixes
P04B7	Fuel Fill Door Position Sensor/Switch Circuit Intermittent/Erratic	4 ranked fixes
P04B8	Fuel Fill Door Position Sensor/Switch Circuit	4 ranked fixes
P04B9	Fuel Fill Door Position Sensor/Switch Circuit Low	4 ranked fixes
P04BA	Fuel Fill Door Position Sensor/Switch Circuit High	4 ranked fixes
P04BB	Fuel Fill Door Lock Control Circuit/Open	4 ranked fixes
P04BC	Fuel Fill Door Lock Control Range/Performance	4 ranked fixes
P04BD	Fuel Fill Door Lock Control Circuit Low	4 ranked fixes
P04BE	Fuel Fill Door Lock Control Circuit High	4 ranked fixes
P04BF	Fuel Fill Door Unlock Control Circuit/Open	4 ranked fixes
P04C0	Fuel Fill Door Unlock Control Range/Performance	4 ranked fixes
P04C1	Fuel Fill Door Unlock Control Circuit Low	4 ranked fixes
P04C2	Fuel Fill Door Unlock Control Circuit High	4 ranked fixes
P04C3	Fuel Fill Door Lock Position Sensor/Switch Circuit	4 ranked fixes
P04C4	Fuel Fill Door Lock Position Sensor/Switch Circuit Range/Performance	4 ranked fixes
P04C5	Fuel Fill Door Lock Position Sensor/Switch Circuit Low	4 ranked fixes
P04C6	Fuel Fill Door Lock Position Sensor/Switch Circuit High	4 ranked fixes
P04C7	Fuel Fill Door Lock Position Sensor/Switch Circuit Intermittent/Erratic	4 ranked fixes
P04C8	Fuel Fill Door Open Request Sensor/Switch Circuit	4 ranked fixes
P04C9	Fuel Fill Door Open Request Sensor/Switch Performance/Stuck Off	4 ranked fixes
P04CA	Fuel Fill Door Open Request Sensor/Switch Circuit Low	4 ranked fixes
P04CB	Fuel Fill Door Open Request Sensor/Switch Circuit High	4 ranked fixes
P04CC	Fuel Fill Door Open Request Sensor/Switch Circuit Intermittent/Erratic	4 ranked fixes
P04CD	Fuel Fill Door Open Request Sensor/Switch Stuck On	4 ranked fixes
P04DC	Fuel Fill Door Position Sensor/Switch Circuit Range/Performance	4 ranked fixes

What this page does not show

This page publishes the fault mechanism and the code index. The licensed dataset adds, for every one of the 15,886 codes, the full authored repair set (56,729 procedures in total) with the fields deliberately withheld here:

Procedures 2..n after the first-listed procedure
Aftermarket parts cost ranges in USD (est_parts_cost_min/max_usd)
Professional labor-hour estimates (est_labor_hours)
Step-by-step diagnostic and repair instructions
Replacement-part mappings and catalog lookups
6,637 manufacturer-specific OEM codes across 32 makes ($149 tier)

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