P0628
Fuel Pump A Control Circuit Low
Computer output circuit
Generic OBD-II
High
What it means
P0628 means the PCM detected an abnormally low voltage (usually a short-to-ground or open) on the fuel pump "A" control circuit. Because this circuit switches the fuel pump, the fault can interrupt fuel delivery — leading to hard starting, stalling, or a no-start. Start by inspecting the pump control wiring and relay for a short before replacing parts.
High
Can I keep driving? Risky — fuel delivery can be interrupted, so the engine may stall or fail to start. Fix before relying on the vehicle.
Common symptoms
What you'll notice
- Hard starting or no-start
- Stalling or cutting out while driving
- Rough running or reduced power under load
- Check-engine light on
Common causes
Most likely first
- Short-to-ground in the fuel pump control wiringLikely
- Faulty fuel pump relay or driverCommon
- Corroded or loose connector in the pump control circuitCommon
- Failed fuel pumpLess often
- PCM control-circuit fault (less common)Less often
How to diagnose & fix
Work through it in order
- Read freeze-frame, then inspect the fuel pump control wiring and connectors for a short-to-ground or damage.
- Test the fuel pump relay and its control signal from the PCM.
- Measure fuel pressure to confirm whether the pump is actually being commanded and running.
- Repair the wiring or replace the relay/pump as indicated. Clear and re-test starting and driving.
FAQ
Quick answers
Is it safe to drive with P0628?+
Not reliably. This code involves the fuel pump control circuit, so the engine can stall or refuse to start. Get it repaired before depending on the car.
Can I just clear P0628?+
It will return as soon as the PCM detects the low circuit again. Repair the wiring, relay, or pump first.
Related codes
Often seen with P0628
Read & clear P0628 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