Relay is good. No power to fuel pump., Now what?? Options

[KaptKaos]

UPDATE: Self inflicted wounds are the worst. She's running.

So the other day when I was charging the battery, I knocked loose one of the 4 leads off of the positive terminal of the battery. I didn't know I had done it.

I am not sure what made me go check the battery, but as soon as I did, the wire dropped out.

Tom - I think that this is what your fuse box is for? Figures.

Thanks for all of your help.

Swapped in known good relay from headlight motor for fuel pump. No dice. No power to the fuel pump.

Fuses all look good. Going to replace the fuel pump one anyway.

Trans ground looks ok, but think I will double-check that.

Is there anything else I should be looking for?

Not sure if this is related, but a few weeks ago, my dash lights stopped lighting. The blinkers and idiot lights work, just not the illumination when the headlights are on.


I actually have some time this morning, and am going to try to diagnose my fuel pump issues.

Got a multi-meter, got some help to turn the key, and got a local VW store I can get a new pump or relay from.

So, which relay on the panel in the engine bay is for the fuel pump? I have a SirAndy Jumper in there (see his classic article).

Also, my multi-meter has ranges. Which setting should I use to test for power to the fuel pump?

Thanks in advance.

[Tom]

With your multimeter on 50 volt scale, check pin 30 on the fuel pump relay for 12 volts. Should be there all the time. If not, your fuse may be bad. Second one from front. If that is good, check for 12 volts at pin 85 of the fuel pump relay with the key to on. If no power, your power relay ( second from front) may be bad or connections bad. If you have that and the ground is good, the relay should operate and provide 12 volts to pin 87 of the fuel pump relay ( same electrically as pin 13 of the 14 pin connector. If you have power here, your fuel pump is bad or has bad connections between pin 13 and the fuel pump.
Tom

[KaptKaos]

With your multimeter on 50 volt scale, check pin 30 on the fuel pump relay for 12 volts. Should be there all the time.

Yes - have 12V there.

If not, your fuse may be bad. Second one from front. If that is good, check for 12 volts at pin 85 of the fuel pump relay with the key to on. If no power, your power relay ( second from front) may be bad or connections bad.

No power there. I swapped the power relay, with no change. So either I have a handful of bad relays (which I don't think that I do) or the problem is elsewhere.

Now where should I look?

Thanks again - this is very helpful.