Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the car's computer thinks the door where you put gas in is open when it shouldn't be.
The car's computer monitors the fuel fill door to ensure it is closed during driving. If the circuit reads too high, it indicates a possible issue with the sensor or switch.
The P04CB code is triggered when the Powertrain Control Module (PCM) detects a high voltage signal from the fuel fill door open request sensor/switch circuit. This could indicate a malfunctioning sensor, a short circuit, or a wiring issue.
• Check Engine Light is on
• Fuel fill door warning light might be illuminated
• Fuel fill door may not lock or unlock properly
• Faulty fuel fill door sensor/switch
• Wiring issues such as a short circuit
• Faulty PCM
PCM: Powertrain Control Module, the vehicle's main computer for engine management
OBD-II: On-Board Diagnostics, a standardized system for vehicle self-diagnostics
• Use an OBD-II scanner to confirm the code
• Inspect the wiring and connectors for damage
• Test the fuel fill door sensor/switch for proper operation
• Repair or replace damaged wiring
• Replace the faulty fuel fill door sensor/switch
• Reprogram or replace the PCM if necessary
• OBD-II scanner
• Multimeter
• Screwdriver set
$100 - $300
Moderate
• Ford Focus
• Chevrolet Malibu
• Toyota Camry
• Regularly inspect the fuel fill door and its components
• Ensure the fuel fill door is closed properly after refueling
• Keep the vehicle's electrical system in good condition
Sensor Issue
• Check if the fuel fill door is properly closed
• Avoid forcing the fuel fill door open or closed
• Consult a professional if the issue persists
Check with your vehicle manufacturer for warranty coverage on emissions-related components.
This code has become more common with the advent of more sophisticated fuel systems and emissions controls.
Moderate – It should be addressed soon to avoid potential fuel vapor leaks.
Driving with this issue may result in increased emissions and potential fuel vapor leaks, which could be hazardous.
• Vehicle parked and engine off
• Access to the fuel fill door
The fuel fill door sensor/switch is typically located near the fuel fill door mechanism.
Q: Can I drive with a P04CB code?
A: Yes, but it is recommended to fix the issue soon to avoid potential fuel vapor leaks.
Q: Will a P04CB code affect my gas mileage?
A: It may not directly affect mileage, but it could lead to emissions issues.
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