P0624
Fuel Cap Lamp Control Circuit
Fuel cap lamp circuit
Generic OBD-II
Low
What it means
P0624 means the ECM has detected a fault in the circuit that drives the fuel-cap warning lamp — the indicator that alerts you to a loose or missing fuel cap. The lamp may not work as intended, but there's no effect on how the engine runs. It's a minor information-system fault, not a drivability problem.
Low
Can I keep driving? Fine to drive — this only affects the fuel-cap warning lamp; the engine and all driving functions are unaffected.
Common symptoms
What you'll notice
- Fuel-cap warning lamp doesn't light when it should (or stays on)
- Check-engine light on (on some vehicles)
- Loose or unsealed fuel cap may not be flagged to the driver
- No noticeable effect on how the vehicle runs
Common causes
Most likely first
- Faulty fuel-cap indicator lamp or bulbLikely
- Wiring or connector issues in the lamp control circuitCommon
- Poor electrical connection at the lampCommon
- Faulty instrument cluster or driver-information moduleLess often
- Fault in the engine control module (ECM) output driverLess often
How to diagnose & fix
Work through it in order
- Check the fuel-cap lamp bulb or indicator and its connection.
- Inspect the lamp control circuit wiring and connectors for damage or corrosion; repair as needed.
- Test the instrument cluster or information module if the lamp still won't respond.
- If wiring and cluster are good, check the ECM output driver. Clear and re-test.
FAQ
Quick answers
Is it safe to drive with P0624?+
Yes. This is a warning-lamp circuit fault with no effect on engine or driving. The only downside is the fuel-cap alert may not work, so double-check the cap is tight.
Can I just clear P0624?+
It will return until the lamp circuit is repaired, but there's no drivability risk in the meantime — just be sure to seat the fuel cap properly yourself.
Related codes
Often seen with P0624
Read & clear P0624 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.
✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX