[Wapiennik]

I copied this article from a different forum. For crediting sake, I've provided the link at the bottom.




You will need a multimeter, +12v power source & ground to test each relay. Connect relay pin 85 to ground. Set your meter for a continuity test, and attach the meter probes to pins 30 & 87. When you apply +12v to pin 86, you should hear an audible "click", and the meter should indicate that 30 & 87 have been bridged (continuity confirmed). If not, then the relay is bad.

If the relays check out okay, there may be a break or short in the wires leading to the pump. Move on to the relay sockets. Test for continuity between the fuel pump relay socket 87, and the green/violet wire at the pump (remember that fuse #18 lies in between these two points). Then test for continuity between the other wire at the pump, and a ground source. If those check out, then the wiring is okay.

On both relay sockets, #30 should be reading +12v at all times. At this point, a fault at the socket or the wiring harnesses is beyond the scope of this writeup, and this is where the setup between the different model E36's will begin to vary. Furthermore, if you haven't found anything wrong by this juncture, then it's no longer a fuel delivery issue, and you should be looking elsewhere for the culprit of your problem.

I hope this information will be useful for you.

Link:
E36 fuel pump: diagnosis & replacement - United Bimmer Community - BMW Forum