Rear wiper motor not functioning at all. Checked the fuse and all seems OK. I have removed all trim on tailgate to gain access to the motor. Removed the connector from the motor and measured voltage with voltmeter and had no success. Just as a sanity check measured the voltage across the tailgate light and get a reading. The wiper arm moves freely when I seperate the rear window, so I doubt the mechanism is blocked. I feel it may be a electrical fault with the rear harness or wiper motor may need to be replaced. Are there any other checks I can do before I order parts or take the car to a bmw dealer?

mine did that , dealer replaced some switch not sure witch though..

Try opening the lid with the glass still closed and the wiper on, if it wipes it must be a damaged wiring problem. No other problems with taillights, rear window heating?

@TLO03: might be the same Fix for many problems. I have had the glass window opening switch replaced and I think that's what they replaced at yours as well. The little switch causes many problems, in my case it prevented the car from remotely locking and the glass popped open when I started the car.

Hi All, thanks for the responses. I have got to the bottom of this issue. I removed the rear hinge clips and wrapping around the harness on the RHS outer. Yes the main brown wires are damaged, infact the rear wiper wire was broken completely. Not fixed yet but atleaset I can order the parts.

Good to hear that you identified the problem. As far as the wires concern, you have a wire repair set link and new hinges link that BMW updated few times to "mitigate" future wire cuts.

Good luck!