P0627: OBD-II code P0627 flags an open circuit at the fuel pump control driver — the PCM can't reliably switch the fuel pump on.
HighPowertrainFuel System
Symptoms
- Check engine light is on; the engine may crank but not start, or stall suddenly while driving.
- Extended cranking before start-up as the pump fails to prime the fuel rail.
- Random stalls followed by a period where the vehicle refuses to restart until the fault clears.
Common causes
- A failed fuel pump control module (FPCM) or fuel pump driver module.
- A broken wire between the FPCM and the fuel pump, common near the tank.
- A failed fuel pump with an internally open winding.
What to do?
Read live fuel pump command with a scan tool. Test fuel pressure at the rail during cranking. Check the pump control wire for continuity from module to pump. Replace the FPCM or pump as diagnostics indicate.