Skip the auto shop - Our mechanics make house calls

Q: No power to the fuel pumps

asked by on

There is no power going to the fuel pumps. We changed all the relays over and still nothing. If we ground the wire at the plug for the computer where you connect an obd reader to we get the pumps to turn on. What would cause this problem

My car has 101000 miles.
My car has an automatic transmission.

This is a tricky issue to diagnose without being there in person. It sounds like the pump may be getting a bad or weak ground. You will need a full wiring diagram and a knowledge of vehicle electronics and schematics to diagnose this. Start by checking power and ground for the pump at the relay terminals, and if you have power and ground, then jump the relay with a wire and see if the pump runs. If it doesn’t, then it may be getting a weak ground somewhere else. Also check all the ground connections for the vehicle, especially ones along the frame of the truck, as these are often subjected to weather elements and may corrode, causing a bad connection. If this yields no results, I would have a qualified professional diagnose the loss of power at fuel pumps and help you move forward with repairs.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Steering wheel noise

Hi there. This comes up quite often on this vehicle. It is caused by a failing column adjusting motor. As the motor and gears start to fail the become stripped and make this noise. They will typically work for a...

Q: my daughter has a 2004 Toyota Highlander. the car wont start so i think it's the fuel pump since i can't hear it run. so once i ge

Check the fuse. There could be more than one relay in the circuit, for example a circuit opening relay as well as an EFI relay. The fault could be due to high resistance in the circuit (even at the relay...

Q: I replaced alternator without disconnecting battery cable won't start?? Not even power at fuse box

Hello, thanks for writing in. You need to check all the main fuses in the engine fuse box. You most likely blew one or more which is why the issue is still occurring. If you need help having the problem...

Related articles

What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
How Long Does a Distributor O Ring Last?
The distributor is part of the ignition system in your vehicle and its purpose is to route high voltage from the ignition coil to the spark plug. The spark plug then...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...