I am trying to diagnois a fuel pump problem. I know the relays are good and when i jump a wire from the front left pin to ground and turn the key on the pump runs. If it is disconnected and the connector is plugged in it does not. Where does the white wire for this pin go to?

Click to view attachment

Goes to the ECU. ECU runs it with key on only for a second or two. Doesn't run the pump again until cranking/running.

So it is safe to assume that there is a problem with that wire somewhere between the board and the ECU? Or is the ECU a possible problem?

Check your fuses on the board as well. One of them is for the fuel pump and can become corroded.

I don't have the pin out for the ECU connector here. Could be either. You can remove the connector on the ECU and ground it there to test it. Could be a bad driver in the ECU. Could even be a connector problem on the ECU, or a bad trace or solder joint. I never opened my ECU, I got rid of it.

FYI just make sure your not chasing something that is not really the problem. I think the pump only runs for 1 second when you turn the key on. Kinda hard to tell.

True, however by grounding the pin he has eliminated that possibility. But for sure check it anyway.

I just pulled the ECU out and traced the wire from the connector on the relay board to the ECU. With my tester is shows continuity and with the key on shows 12 volts. It seems like that is correct.However I have the fuel line from the pump going to a glass bottle and it is getting no fuel in the bottle unless I jump the pin to ground.

Sounds correct. You are seeing the 12 through the coil of the relay. My guess is you have a bad ECU. Can't hurt to open it and see if anything is visibly wrong. Or see if anyone close to you has a ECU you could try.

underthetire thanks for all your help and quick responses. There is a member local to me with a rebuilt ECU sitting in his garage. I will swap them out and see what happens.

No problem. I actually have to go work now anyway. Good luck.

This may help:

http://members.rennlist.com/pbanders/FPChecklist_frame.htm

RicD just had the same problem switched out the ECU, works now.

Problem found. It's running again.

Thanks everyone.

Well?

FYI just make sure your not chasing something that is not really the problem. I think the pump only runs for 1 second when you turn the key on. Kinda hard to tell.
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This was the problem all along. A member brought over a remanufactured ECU and we plugged it in. He could here the relay click and the pump run. Ok, ECU is bad. Just to be sure we plugged my ECU back in and again he could here the relay click and the pump run.

The problem all along was that by myself in the car I could not here the pump run and thought there was an actual problem, when there was not.