When I bought it, the most obvious fault was the passenger side door mirror being wrapped with black tape. Not idea but certainly not a deal breaker for me. Years before, I'd changed the same mirror on a 306, so I didn't think it held any worries.
Needless to say, the black tape didn't look too bad, and it worked OK so I left well alone. Part of the problem was that the 306 replacement mirror had been an aftermarket one. It fitted perfectly, but had a black shell, not maroon to match the car.
I decided that I preferred tape to a non-matching mirror. Anyway, it worked.
Well, it worked until recently. After all this time, the tape had started to let go. The final straw was when I knocked it while washing the car. Time for new tape. I didn't have any proper gaffa tape to hand so used some stuff from Wilco. Black and smooth, it looked great. Sadly, the glue gave up after a couple of days.
Unhappy, I decided to use silver gaffa and cover it with the black. First, I peeled and cut away the old tape - at which point I realised that the problem wasn't as bad as feared.
Basically, the mirror plastic was complete, but some fixings inside had broken. The tape tied the plastic down to the metal arm.
Spotting some star-topped fixings in the bottom, I started to take the thing to bits but it quickly became apparent that this was going to be a fiddlier job than expected. Better done on the bench.
Removing the mirror unit is simple.
Unclip the inner plastic panel. Undo the big white electrical connector and then use a T15 star headed screwdriver to undo the three bolts arrowed. The unit can then be wiggled off from outside and the thing taken to the bench.
To be honest, detailes of my repair won't help anyone much, but some general notes might.
There are two T15 bolts in the bottom but you can't release the plastic with the mirror in place. It's held with a spring clip which is difficult to fathom out but if you swing the mirror so the outer edge is as far forward as possible, a small screwdriver can flick the wires out of the clip. You can see them in the photo above which should help.
Incidentally, the brown wires are for the heater. Heated wing mirrors - how cool is that?
Removing the plastic casing is made easier by releasing the motor unit using a T10 star screwdriver. It stayed intact for me with the three long screws removed.
Inside the mirror, at the bottom, there is an odd shaped flappy thing not obviously attached to anything. From the 306 experience, I know this to be the exterior temperature sensor. I know this because the aftermarket mirror didn't include one and I had to hack the old sensor into the new wiring...
Anyway, using copious amounts of epoxy glue, I repaired all the broken bits of plastic and my mirror looks as good as a 19 year old mirror can be expected to. Sensible people would of course just bin the unit and replace it whole - a primered version can be bought for 30 quid. Painting the top would take longer than swapping the units over.
The moral of the story is that some jobs aren't as complicated as they might appear. I could have done this years ago!
Legal note: This is an accurate description of what I did. I am not a professional mechanic and these notes are offered for entertainment only. If you chose to follow them and things don't work, it's not my fault. Sorry. If you are at all unsure then get a professional to do the job. The car used was a 1996 UK spec 206, other models may be different.