My 1989 745 GL with B234F motor developed an interesting problem. About 5 minutes after I turn on the headlights the front wipers come on. If I use the turn signal before then they also come on. The wiper control won't turn them off! If I turn off the headlights the wipers go off. With the lights off the wiper control operates normally. Any suggestions? Thanks, Denis

Wow...I just had my front spoiler fog lights replaced on a 1987 Turbo Wagon I recently got, and when I left my mechanic, I turned on the headlights and the wipers also came on!! By themselves they are fine, parking lights on, fine, but as soon as the headlights come on both front and rear wipers start going and I cannot turn them off...
Is this really a grounding issue?! Man, how in the world is this corrected?!
Any more ideas will be appreciated!

This sort of problem can also be caused by poor grounding of the steering column, but as I recall it usually happens in conjunction with the honking of the horn. The two steering column anchor bolts (shear bolts) tend to loosen with age, causing poor grounding along with the steering wheel wanting to shift slightly from side to side.

The lights are grounding through the washer pump wiring and backfeeding to the wiper relay. Check the grounds on the fender behind the lights on the waqsher reservior side. While you're at it, check the other side too.

Thank you!!! My problem was solved when I cleaned and re-attached the washer pump ground and the fog lamp ground connections on the fender! Thankfully it was not the steering column...
My mechanic was also amazed at the resources at brickboard!

My son had a similar problem with his 1987 744T just after I helped him install headlight relays. Operation of the right front turn signal would operate the wipers. I investigated and found the trun signal ground had been pulled off the ground tab. Re-connecting it solved the problem. Check your headlight grounds.

Denis -

In addition to reading the FAQ's here, check out this URL:

http://www.babcox.com/editorial/ic/ic129744.htm

It's UnderhoodService.com's article:
"Volvo Electrical System Service: In Search of Good Grounds", Bob Kraft, ImportCar, December 1997

This should address your problem!

- Al