Thanks in advance for your opinions and thoughts on this......

Some months ago my car was gently side swiped and I had to replace my dirver side mirror assembly in its entirety. Immediately after that the side mirror switch began to malfuction. I took my car my back and said that it must have been something they did with the mirror assembly but after checking the switch they said it's more likely that the mirror switch went bad (Odometer now @ 207K miles).

Today, they got the switch and replaced the part but the same problem persisted. They said the part was bad (it was a used part) and ordered another one. They tried again and that one didn't solve the problem either.

So, I asked again, don't you think it's something the shop did while replacing my driver side mirror assembly? They said it's impossible as the whole assembly comes in one piece and the mirror motor is plugged into a single piece of wire. Besides, they said, the passenger side mirror do not correctly respond to the switch either. As such, they concluded that perhaps I should just get a new part which is a bit more expensive and see what happens.

I've been going to this shop for quite some time and have no reason to doubt the assessment. I also took a look at the part diagrams and see that there can't be too many associated parts with mirror assembly that can make either side go bad in one fell swoop.

However, what is the likelyhood of my getting defective parts two times in a row even if it's a used part. Then, if not the switch, what other part might be at fault?

 

If you are using "salvaged" parts, then it is more likely that you got a faulty switch both times. If the switch was "new" I would be looking for something else to be wrong. I agree that it is unusual to have two faulty switches in a row - but that's the risk when you go with used parts.
Since both mirrors are acting up, I think your mechanic is correct that it is something common to both mirrors (i.e. the switch, or common power/ground circuit). I don't know if there is a relay or some other item that is common to both mirrors. Do you have the heated mirrors?

Perhaps water got into the connector when the drivers mirror was broken and corroded the wire terminals causing high resistance. Possibly that is affecting the "circuit" and messing up both mirrors. But I would still replace the switch as I think it is the more probable failure.

 

Can he momentarily short certain wires? I would break open the old switch and see or look up wiring diagram.

Salim

 

both you are correct. they suspect a short somewhere and broke open the old switch to see if wiring is fried somewhere. more report later when it is indeed fixed.

 

as it turns out, the replacement mirror was bad. it was constantly causing a short, in turn, frying the switch. So it wouldn't have mattered how many switches were replaced. So I'm having the shop replace the mirror.

 

Thanks for the update! Glad to hear you found the problem!