Fuel pump relay?

[Audi body]

Car died and won't start. Checked everything and got to the fuel pump. Didn't have a meter so I ran a couple wires to the fuel pump and the pump started running. Car started and ran fine. Checked the fuse and it's good. I'm even getting power to the fuse slot. Checked for voltage at the pump and I'm not getting anything. Is this pointing me at the fuel pump relay?

[coffeysm]

Sounds like it could be the relay or the wiring to the pump. You can test the relay by looking for continuity between two of the poles, which it should exist. Then you put power to these two poles, it will click, and check for continuity on the other two poles to make sure it can pass current. That's for a four pole relay, I don't remember how many the Audi relay has though, I had to go through this same issue last week. I have a quattro though and it ended up being my suction jet pump causing in the tank causing a no start condition.

You can also try jumping the pins in the fuse panel where the relay sits to test the wiring, but I don't like doing this if you make a mistake you can end up frying the ECU.

[Audi body]

Yeah ill skip the jumping part. Definitely need to open the ecumenical box and check the relay. I wish I had a wiring diagram to trace the power. I thought the power went from the fuse to the pump but I guess I'm wrong

[diagnosticator]

The ECU power supply relay in the ECU box, powers the J17 fuel pump relay under the dash panel. If the ECU power supply relay was not working , there would be no spark either.

[Audi body]

Alright. So I guess it's time to figure out what's going on. Anyone have a wiring diagram for the fuel system?

[old guy]

Read through this rather lengthy thread. There is a ton of diagnostic information pertinent to your issue including how to isolate the fuel pump relay as well as the wiring from the relay to the pump. The fuel pump relay gets energized by the ECM master power control relay. Clicky click®

[diagnosticator]

Correction: there are two relays involved, there is the ECU power supply relay in the ECU box, and the fuel pump relay under the drivers side dash panel, the left most relay in the horizontal row of relays. The wire to the fuel pump from J17 fuel pump relay is 2,5 mm Green/Yellow. The ECU power supply relay provides power to the fuel pump relay then to the fuel pump via fuse 28. It's possible the fuel pump relay is faulty.

[diagnosticator]

Yeah ill skip the jumping part. Definitely need to open the ecumenical box and check the relay. I wish I had a wiring diagram to trace the power. I thought the power went from the fuse to the pump but I guess I'm wrong

It does. The 4mm Green wire at the J17 fuel pump relay goes to fuse 28, then via a 2.5 mm Green/Yellow wire to the fuel pump.

[Audi body]

At the fuel pump it's a brown wire. Ok old guy I'll look through the thread. I appreciate the help

[Audi body]

Oh I must be looking at the ground wire. Stupid mistake I'll check and report back.