The folding mirror has a clicking sound

Yes

That is usually a sign the load is too much for the fold in/ fold out mechanism, I would try some WD 40 spray in the pivot area and let it soak in for a while and then see if it helps, if not then it maybe time for a new mirror head assembly or quit using the auto close feature.

Does it do this when adjusting the mirror or only during the folding operation?

taver91, mine does it only during folding operation. The unit that holds the mirror and folds (not sure what that is called) makes the clicking sound as if it is trying, but does not stay open fully. I can adjust mirrors and the fuse is fine for them. Just not sure what to repair/replace to make the folding unit work properly.