P0627Powertrain
Powertrain · SAE
Fuel Pump A Control Circuit
Meaning
The ECM detects a generic electrical fault in the electric fuel pump control circuit (drive signal from the control module to the pump or relay). The circuit does not respond correctly to the command signal.
Common causes
- Open in the control wiring between ECM and relay/pump
- Short circuit in the control circuit
- Faulty fuel pump relay
- Loose or corroded control module connector
- Internal failure of the pump control module (if fitted)
Symptoms
- Check-engine light on
- No-start or hard start
- Pump does not activate at key-on
- Sudden engine stall
- No fuel pressure
Severity
High: pump failure prevents starting or maintaining engine operation; immediate attention required.
What to do
- Verify the ECM command signal is present at the pump circuit
- Check the fuel pump circuit relay and fuse
- Inspect control wiring for opens or shorts
- Verify voltage at the pump connector with relay energised
- Replace the faulty relay or identified component