P0627: Fuel Pump A Control Circuit/Open

What 'fuel pump A control circuit' means differs by maker: at GM petrol engines it is the control line from the engine module to the fuel pump relay (high-side driver), at GM's LML diesel the lift pump, at Ford petrol engines with a pump driver module the secondary circuit from that module to the pump (reported as a duty cycle on a monitor line), and at Ford's 6.7 L diesel (F-650/750) the high or low side of the pump relay. P0627 is the open or general circuit fault. GM measures with the relay driver on and sets the code at 200 kΩ or more after 8 of 10 samples at 250 ms – after two trips in 2018, in the first trip in 2025; some modules also set P0629. Ford's petrol pump module reports an open, short or overheating in its secondary circuit (2012: 80 % duty cycle, 2–5 s), Ford's 6.7 L diesel an open relay side within 0.2 s. Without the pump the engine does not start or stalls.

Symptoms

• Engine does not start or stalls
• Lack of power or stumbling under load
• Pump not audible with ignition on
• Check engine light on

Most likely causes

• Fuel pump relay or pump driver module faulty
• Wire or connector to relay or pump open or corroded (tank, underbody)
• Fuel pump itself (winding open, overheated)
• Fuse or ground point
• Driver in the engine module faulty

What to check, in order

Start with the simplest. You can tick off each step.

1. Check the pump's fuse, relay, and connector
2. Check the continuity of the wire between the component and the control module.
3. Replace the filter if it is due for maintenance
4. Compare commanded and actual pressure in live data
5. Measure the pressure with a suitable gauge
6. Check the sensor and regulator before replacing the pump

Good to know

• Repair difficulty: medium
• It can trigger limp mode.
• It affects emissions.

What each character of P0627 means

• P: Powertrain: engine and transmission
• 0: Generic code: same on every make
• 6: Control modules and outputs
• 27: Specific fault in that system

Frequently asked questions

Can I keep driving with code P0627?

Avoid long trips and hard acceleration. If you smell fuel or the car stalls, do not continue.

What causes code P0627?

The most common causes are: fuel pump relay or pump driver module faulty; wire or connector to relay or pump open or corroded (tank, underbody); fuel pump itself (winding open, overheated).

Related codes

• P0628Fuel Pump A Control Circuit Low
• P0629Fuel Pump A Control Circuit High
• P062AFuel Pump A Control Circuit Range/Performance
• P0230Fuel Pump Primary Circuit
• P025AFuel Pump Module A Control Circuit/Open
• P064AFuel Pump Control Module A

Sources

• law.cornell.edu: 13 CCR 1968.2
• gsi.ext.gm.com: 18OBDG03A Engine Diagnostics
• gsi.ext.gm.com: 14OBDG10 Engine Diagnostics
• fordservicecontent.com: obd summary diesel 2023

Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.