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 not working right. It might think the door is open when it shouldn't be.
The vehicle's computer has detected a low voltage signal from the fuel fill door open request sensor or switch circuit.
The P04CA code indicates that the Powertrain Control Module (PCM) has detected a low voltage condition in the circuit that monitors the fuel fill door open request sensor or switch. This sensor or switch is responsible for informing the PCM whether the fuel fill door is open or closed. A low voltage signal typically means there is an issue with the sensor, switch, or the wiring in the circuit.
• Check Engine Light illuminated
• Fuel fill door not responding
• Inaccurate fuel door status display
• Faulty fuel fill door sensor/switch
• Damaged or corroded wiring or connectors
• Faulty PCM
PCM: Powertrain Control Module
OBD-II: On-Board Diagnostics, second generation
• Use an OBD-II scanner to confirm the code.
• Inspect the fuel fill door sensor/switch for damage.
• Check wiring and connectors for corrosion or damage.
• Replace the faulty fuel fill door sensor/switch.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the PCM if necessary.
• OBD-II scanner
• Multimeter
• Screwdriver set
$100 - $300
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regularly inspect fuel fill door components.
• Keep connectors clean and free of corrosion.
• Ensure proper closure of the fuel fill door.
Sensor Issue
• Check the fuel fill door for any visible damage.
• Ensure the fuel fill door is closed properly after refueling.
Check with your vehicle manufacturer for warranty coverage on emissions-related components.
This code has been associated with vehicles that have electronic fuel fill door systems and has been noted in models with advanced fuel management systems.
Low – This issue does not immediately affect drivability but should be addressed to ensure proper fuel system operation.
Ignoring this code may lead to fuel system issues; ensure repairs are performed by a qualified technician.
• Vehicle ignition in the ON position
• Fuel fill door operation test
The fuel fill door sensor/switch is typically located near the fuel cap area, integrated into the fuel door mechanism.
Q: Can I drive with the P04CA code?
A: Yes, but it's best to have it checked soon to avoid potential fuel system issues.
Q: Will this code affect my fuel economy?
A: Not directly, but unresolved issues could lead to other problems affecting fuel efficiency.
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Fitment Required · Vehicle-fitment part
Relevant for some EVAP leak codes where the fuel cap or sealing surface is part of the problem.
Some EVAP leak faults involve the fuel cap or its sealing surface.
Fuel caps vary by vehicle and should be matched to the exact application.
View options on AmazonThese parts may be related to this fault category, but a code by itself does not confirm exact fitment or guarantee that replacing a part will solve the problem.