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 light on your dashboard that tells you if your gas cap is loose or missing. It's like when a light bulb in your house doesn't work because the switch is broken.
The P0624 code indicates a malfunction in the circuit that controls the fuel cap warning lamp, which alerts the driver if the fuel cap is not properly secured.
The P0624 code is set when the Powertrain Control Module (PCM) detects a fault in the circuit responsible for illuminating the fuel cap warning lamp. This could be due to an open or short circuit, or a failure in the lamp itself.
• Fuel cap warning lamp does not illuminate
• Check engine light may be on
• No warning when fuel cap is loose
• Faulty fuel cap warning lamp
• Open or short circuit in the fuel cap lamp circuit
• Faulty Powertrain Control Module (PCM)
PCM: Powertrain Control Module
OBD-II: On-Board Diagnostics, Second Generation
• Check the fuel cap warning lamp for proper operation.
• Inspect the wiring and connectors in the fuel cap lamp circuit.
• Test the PCM for faults.
• Replace the faulty fuel cap warning lamp.
• Repair or replace damaged wiring or connectors.
• Replace the PCM if necessary.
• Multimeter
• OBD-II scanner
• Basic hand tools
$50 - $200
Moderate
• Ford Focus
• Chevrolet Silverado
• Toyota Camry
• Regularly check the fuel cap for proper sealing.
• Inspect wiring for wear and tear.
• Ensure connectors are secure and free of corrosion.
Electrical Circuit Issue
• Ensure the fuel cap is tightly secured after refueling.
• If the warning light does not function, have it checked by a professional.
Typically covered under basic vehicle warranty if the vehicle is still under warranty period.
This code has been more prevalent in vehicles with electronic fuel cap monitoring systems introduced in the early 2000s.
Low – This issue does not affect vehicle performance but should be addressed to ensure proper warning system function.
Driving without a functioning fuel cap warning system can lead to increased emissions if the fuel cap is not secured properly.
• Vehicle ignition on
• Fuel cap properly secured
Typically located on the dashboard, integrated within the instrument cluster.
Q: What happens if I ignore the P0624 code?
A: Ignoring this code may result in not being alerted to a loose fuel cap, which can increase emissions and potentially trigger other emission-related codes.
Q: Can I drive with a P0624 code?
A: Yes, you can drive with this code, but it's recommended to fix it to ensure your vehicle's warning systems are functioning properly.
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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.