Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means there's a problem with the sensor that tells the car if the fuel door is locked or not. It's like when a light switch doesn't work right, and you can't tell if the light is on or off.
The P04C4 code is triggered when the Engine Control Module (ECM) detects an issue with the range or performance of the fuel fill door lock position sensor or switch circuit.
The fuel fill door lock position sensor/switch is responsible for detecting the position of the fuel door lock. If the ECM receives a signal that is out of the expected range or not performing as anticipated, it will set the P04C4 code. This can be due to electrical issues, mechanical failure, or sensor malfunction.
• Check Engine Light is on
• Fuel door may not lock or unlock properly
• Unusual noises from the fuel door area
• Faulty fuel fill door lock position sensor
• Damaged or corroded wiring or connectors
• Mechanical failure of the fuel door lock mechanism
ECM: Engine Control Module
OBD-II: On-Board Diagnostics II
• Inspect the fuel fill door lock position sensor for damage.
• Check the wiring and connectors for corrosion or damage.
• Test the sensor with a multimeter to ensure it is within specification.
• Replace the fuel fill door lock position sensor if faulty.
• Repair or replace damaged wiring or connectors.
• Fix or replace the mechanical components of the fuel door lock.
• Multimeter
• Screwdriver set
• OBD-II scanner
$100 - $300
Moderate
• Ford Focus
• Chevrolet Malibu
• Toyota Camry
• Regularly inspect the fuel door and lock mechanism.
• Keep the area clean and free of debris.
• Ensure connectors are securely attached and free of corrosion.
Sensor Issue
• Check the fuel door operation regularly.
• Listen for unusual noises when locking or unlocking the fuel door.
Check with your vehicle manufacturer for warranty coverage on sensors and electrical components.
This code has been more common in vehicles with electronic fuel door locks introduced in the last decade.
Low – This issue does not affect drivability but should be addressed to ensure proper fuel door operation.
Ensure that repairs are performed by a qualified technician to prevent further damage or safety hazards.
• Vehicle parked with ignition on.
• Fuel door lock engaged and disengaged.
The fuel fill door lock position sensor is typically located near the fuel door latch mechanism.
Q: Can I drive with a P04C4 code?
A: Yes, but it's advisable to fix it to ensure your fuel door locks properly.
Q: Will a P04C4 code affect my fuel economy?
A: No, this code does not impact fuel economy.
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