I had my wing mirror go faulty recently it was grinding away when folding in and out with the powerfold function. Seems a pretty common failure I didn't hold much hope in a repair but a search on the bay found a repair kit consisting of the worm gears and electric motor pinion shaft gear for less than a tenner, so not much to lose iv stripped it down and found the pinion shaft gear to be the 1 which is worn down causing the grinding noise. Can't get it off with the kit iv got so have orderd a removal tool.

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