P0627 code: Fuel Pump A Control Circuit/Open
P0627 means fuel Pump A Control Circuit/Open. The code says where to look, not what failed — the fix depends on which cause your car actually has.
What P0627 means
P0627 means the computer found an open circuit — a break — in the wiring it uses to control the fuel pump. The pump is usually switched through a relay, and on many vehicles a dedicated fuel pump driver module; a failed relay, a blown fuse, a corroded connector, or a broken wire anywhere in that chain can set this code. When the control circuit is truly open the pump doesn't run, and the engine stalls or won't start because it isn't getting fuel. Intermittent breaks cause the more maddening version: random stalling that recovers, especially over bumps or in damp weather. The relay is the cheap, common suspect and a sensible starting point; the driver module and the wiring to the tank are the deeper checks.
P0627 symptoms
- Engine cranks but won't start
- Sudden stalling, sometimes intermittent
- No fuel pump hum from the tank when the key is switched on
- Long cranking before start
- Check-engine light
What it costs to fix P0627
Typical range: $20–$600 · about ~0.2–2 hrs of labor
| If the cause is… | Part | Labor |
|---|---|---|
| Fuel pump relay | $15–$50 | ~0.2–0.5 hrs |
| Wiring / connector repair | $5–$100 | ~0.5–2 hrs |
| Fuel pump driver module (where fitted) | $100–$400 | ~0.5–1.5 hrs |
A relay is cheap and quick; wiring repairs depend on where the break is; a fuel pump driver module is the pricier electronic fix. If diagnosis shows the pump itself has failed, that's a separate and larger job — this code is about the control circuit, so test before replacing the pump.
The price swings on which cause it turns out to be — so confirm the cause before paying. Diagnose P0627 for my exact vehicle →
How to fix P0627
Easy — basic tools, most owners can do this
- Listen for the pump's key-on prime
Switch the ignition on without starting and listen near the fuel filler or under the rear seat for a brief hum. A pump that primes suggests an intermittent break; silence plus a no-start means the circuit is open right now, which actually makes the fuse, relay, and module easier to test while the fault is present.
- Check the fuse and swap the relay
Find the fuel pump fuse and relay from the owner's manual or fuse-box lid. Test the fuse with a meter rather than by eye, then swap the relay with an identical one from a less critical circuit. If the pump comes back, replace the relay, and inspect the socket for melted or corroded terminals.
- Reset the inertia switch where fitted
Some vehicles have a fuel cut-off (inertia) switch, often in a footwell, kick panel, or trunk, that trips on a hard jolt and resets with its button. Depending on the design, a tripped switch can open the circuit the computer is watching, so check it before testing further.
- Test the control signal at the relay or module
Using a wiring diagram, check that the relay coil or pump driver module has power, and that the computer's control wire switches during the key-on prime or when commanded with a bidirectional scan tool. A signal leaving the computer that never arrives at the relay means a broken wire between them.
- Check the driver module and pump connector
On returnless systems the pump is run by a driver module, often mounted near the tank or under the rear of the vehicle where water and road salt attack its connector. Check its power, ground, and output at the pump connector; good inputs with no output mean a failed module, while a pump that draws no current needs replacing.
DIY or shop? Fuse, relay, and inertia-switch checks are among the simplest electrical diagnoses on a car, and they resolve a good share of P0627s. Driver modules are often bolt-on parts reachable from underneath or behind trim. It becomes shop work when the pump itself has failed, since that usually means dropping the tank or working through an access panel around gasoline vapour, or when the break is hidden in the body harness. Never bridge the relay socket without a fused jumper.
Tools for the DIY steps: Digital multimeter · Test light · Spare relay matching the original · Wiring diagram for the pump circuit · Bidirectional scan tool
Not sure which step applies to your car? Get the likely cause for your exact vehicle before buying anything for P0627.
Start a case with P0627 and your car. Redline weighs these causes against what your car shows, and names the check that would settle it before you buy parts.
Can I drive with P0627?
Redline can’t determine from a symptom or code alone whether your car is safe to drive.
P0627: common questions
Can I drive with P0627?
Redline can't make that call from the code alone. The fault is in the circuit that runs the fuel pump, and an intermittent break can cut fuel without warning, causing a sudden stall or a no-start. Prompt diagnosis is strongly advised, and if the car stalls, stop driving it.
Is P0627 the fuel pump itself?
Not necessarily — the code points at the control circuit: relay, fuse, wiring, or driver module. Those are all cheaper than a pump. A good diagnosis confirms whether the pump ever receives power before anyone drops the tank.
What's the cheapest thing to check first?
The fuel pump relay and its fuse. Relays are inexpensive, commonly fail, and on many cars you can swap in an identical relay from another slot as a quick test.
Why does my car stall randomly with this code?
An intermittent open — a loose pin, a corroded connector, a chafed wire — cuts pump power momentarily, the engine dies from fuel starvation, and then it may restart once contact returns. Bumps, heat, and moisture often trigger it, which is a useful clue for the diagnosis.
Symptoms that trigger P0627
Drivers who get this code often notice one of these. Each has its own causes and cost guide:
Related trouble codes
Don’t have a scanner yet? A ~$25 Bluetooth adapter reads codes like P0627 from your phone. See our guide to the best OBD2 Bluetooth adapters. Run a repair shop? See Redline for shops.
Generic OBD-II reference. Manufacturer-specific behavior varies. Confirm with a scan tool and, for safety-related codes, a professional inspection. Cost ranges are reference ranges, not quotes.
Seeing P0627 on your car?
Every problem becomes a Case. Tell Redline what the car is doing: it shows what the evidence supports, what’s still missing, and what to check next, before you approve a repair.
“Inner pad ~1 mm. Outer pad 3 mm.”
Next: check the slide pins move freely before buying parts.