Rear Wiper Positioning

[csl]

Any ideas how to resolve this please :

Rear Wiper (E34 Touring) comes to rest in a different position each time.
I've tightened the window latch, tightened the wiper mechanism cable but no luck. The pin isn't jumping out of the hole.

??????

For anyone who may be interested, I found the solution. Broken red/black wire in the r/h side harness of the trunk lid.

[DanQ]

Thanks for the solution. I thought that the odd position was a "feature" that i'd have to live with.