P0629
Fuel Pump A Control Circuit High
Fuel delivery
Generic OBD-II
High
What it means
P0629 means the ECM has detected a high-voltage condition in the control circuit for fuel pump 'A'. This circuit commands how the pump runs, so a fault here can disturb fuel delivery — causing hard starts, stalling, or a no-start. Because it can leave the vehicle unable to run, it should be diagnosed promptly.
High
Can I keep driving? Risky — a fuel-pump control fault can cause hard starts, stalling, or a no-start. Address it before relying on the vehicle.
Common symptoms
What you'll notice
- Check-engine light on
- Hard starting or no-start
- Stalling or loss of power
- Fuel pump running abnormally, or inadequate fuel pressure
Common causes
Most likely first
- Faulty fuel pump relay or driverLikely
- Short to voltage or open in the fuel-pump control wiringCommon
- Failed fuel pump (driver) control moduleCommon
- Corroded or loose connector in the fuel-pump circuitLess often
- ECM fault (rare)Less often
How to diagnose & fix
Work through it in order
- Read freeze-frame data and check fuel pressure to gauge delivery.
- Inspect the fuel pump relay and control wiring for a short to voltage or open.
- Measure the control-circuit voltage against specification.
- Test the fuel pump control module (where fitted) and the pump itself.
- If wiring and components are good, have the ECM tested. Clear and re-test.
FAQ
Quick answers
Is it safe to drive with P0629?+
Not reliably. A fuel-pump control fault can leave you stranded with a no-start or stall. Get it diagnosed before depending on the car.
Can I just clear P0629?+
It will return while the control circuit reads high. Repair the relay, wiring, or control module first.
Related codes
Often seen with P0629
Read & clear P0629 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