BMW Repair: Intermitant windsheild wipers, windsheild wipers, windshield wipers

Question
Intermittent windshield wipers

I have a 2000 540i.  Recently the windshield wipers and washer have taken to stopping all of a sudden while driving down the highway.  After waiting one to ten minutes it starts working again often for a long period of time.  There doesn’t seem to be a correlation between length of time it’s been on before stopping.  The washer also doesn’t work although on two occasions it has worked for a second or two before stopping after the wipers die.  I’ve taken it in to a BMW dealer (happened to be working at the time) and they can’t find anything wrong.  It’s incredibly dangerous and judging from the number of questions posted concerning BMW wipers, I’m not alone.  Has anyone found what appears to be a common problem.

Thanks for any help on this.


Answer
I had a similiar problem on a 325i I had.  Chased it forever, before finding a relay that was flaky.  On the 325, it was mounted under the floor foot rest.  Once I replaced that, I had no problems.

Sorry, don't have an e39 wiring diagram to work with, but my guess would be that