E34 wipers problem

[shiftfan]

Hello!
It all began when i wanted to see if my window washer pump works, and suddenly a fuse "died".I replaced it , and the wipers worked only on first , and last speed.At that time i thought it must be a relay and i put the problem on hold.I had some kind of a phone electrical system running through the car , which i wanted to get rid of, and after that the brake lights ,parking lights, wipers and side mirrors stopped working.I pushed a connector left side under the steering wheel the parking lights started to work, the electrical mirrors too, but i think in reverse,...anyway regarding the wipers....

I checked :
the wiper motor and it's k
all the fuses are k (including the second power box too)
the relays related to the wipers and they seam to be k. (2 yellow relays near the second power distribution box under LH of rear seat)
wiper switch in the steering and it's k
-btw i have a m50b20 from 91
Sorry for my bad english.

Please help .Thank you.

[genphreak]

#1 root cause for what you describe is the 80A relay. Common fault. It is near the battery under the rear seat in most e34s, but on M20 and M50 powered cars it is in a big black plastic case on the frame over the front spring support. These fuses can die with age and look okay, and intermittently fail as well. Check the fuse on the firewall and also for inline fuses on the thicker wires that come from the battery. There may also be one under the backseat, I can't remember.

However a common fault causing such gremlins that any e34 owner must be aware if is water. An older e34 may have had windscreen replaced, have rust around the window (rare, it is only caused by windscreen repairers using bad tools and leaving bare metal to rust in the wet spots around the window). Or it cna be a blocked sunroof drain which causes water to seep in down the turrets, and secretly end up soaking into the foam under the carpet. An e45 can carry 50L of water in the carpet without you knowing. Danger signs are excessive condensation on the inside of ANY window in the early morning.

Check that the entire area under the rear seat is clean and dry, and free of rust around the connectors *underneath* the Relay Module, General Module, and Relay case. If you have water under there check the wiring loom- it may need replacing as corroded connectors are not easy to troubleshoot or repair.

[shiftfan]

I have the battery under the backseat , fuse was near it's intact.
I checked the RM,GM,and relay connectors and they are k ,i think i checked every possible continuity of the wires involved in the wiper system and after 2 hours, something "hit me "). The nr1 fuse , F1 should have 12V on but i hadn't,i put 12V on it with an wire from F2 , and the wipers started working.Under the F1 there are 2 wires : violet, and violet with yellow, neither of the had 12v on it,.Do you know which one should have, so can make a permanently fix ?
I didn't checked the carpets yet, but i will do it very soon.

[shogun]

wiring diagrams are here
E34 (1988 to 1995 5 Series) Wiring Diagrams

[genphreak]

sorry I meant to say check both the 50A and 80A fuse in that last post. If you're battery is uner the rear seat, expect the 50A one to be 'old' and dead. to check, put the wipers on mid position (no go), turn on the ignition and go and fiddle with the in line 50A fuse to see if they start working. If intermittently failing, replace. Check continuity or just replace regardless.

To test I don't bother inspecting the fuses, I just jumper them (with another known good 80A fuse) to know they are good.