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Marty
Marty, Mercedes Technician
Category: Mercedes
Satisfied Customers: 53594
Experience:  Bosch Certified Master Tech. Over 35 years experience.
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I have a 2002 AUDI A6 i dont have any power at my fuel pump

Customer Question

Hi my name is ***** ***** have a 2002 AUDI A6 i dont have any power at my fuel pump fuse
Submitted: 1 year ago.
Category: Mercedes
Expert:  Marty replied 1 year ago.

Hi Willie, are you checking fuse 28 for voltage when cranking the motor? If you have no voltage I'd try a new fuel pump relay.

Expert:  Marty replied 1 year ago.

The relay is located on the relay panel under the left side of the dash.

Expert:  Marty replied 1 year ago.

Click on the attachment below.

Customer: replied 1 year ago.
we replaced fuel pump relay.
Expert:  Marty replied 1 year ago.

Have you checked your inputs to the relay? You should have power on pin 17 and 19 with the key on.

Customer: replied 1 year ago.
it is power on 17 & 19 with the key on
Expert:  Marty replied 1 year ago.

Will the car run if you bypass the fuel pump relay?

Customer: replied 1 year ago.
how to bypass the relay.
Expert:  Marty replied 1 year ago.

You will need to remove the relay and place a fused jumper lead from terminal 17 (power in) to terminal 20 and 23 (power out).

Customer: replied 1 year ago.
HI MARTY it wont run with the jumper
Expert:  Marty replied 1 year ago.

Ok, so it sounds like you have more than a fuel pump problem. The ECU energizes the fuel pump relay and initiates spark and fuel injection. Have you tested for spark and injector pulse? Will it run if you spray ether into the air intake?

Customer: replied 1 year ago.
I haven't checked injector pulse, but I dont have spark. And the check engine light doesnt come on when you turn the switch on.
Expert:  Marty replied 1 year ago.

Sounds like there is no power to the ECU or the ECU is bad. I'd start by checking for power at the ECU.

Customer: replied 1 year ago.
Is this where you check pins # ***** 55, 56, and 62 for voltage. If so they all have voltage & pins 1 & 2 has ground.
Expert:  Marty replied 1 year ago.

I'm not sure if those are the correct pins but if you have power and ground to the ECU and no spark, fuel pump or injector pulse you may have a bad ECU. Have you checked the timing belt to see if it broke? Checked compression?

Customer: replied 1 year ago.
HI MARTY that is all good the car started at the begaining to run rough and then started to skip and then it would not even crank one TEC. said it could be the switch no one has been able to help.
Customer: replied 1 year ago.
Good Morning Marty i was just wondering if you were still with me, Last I had said the timing belt and compression are OK it had started to skip and it got where it would not run. IF you dont have the time to help i understand, but could you refer me to another TEC that could help me THANKS,
Expert:  Marty replied 1 year ago.

Hi Willie, I'm out of the office until Monday. I will opt out for now and check back with you on Monday.

Customer: replied 1 year ago.
HI Marty i was wondering if you got anything else on the AUDI
Customer: replied 1 year ago.
Marty did you find anyone to help me i am still here.