I called the dealership and they said the part is $180+ and then labor to run wire to add just the driver's side rear mirror visor, so it has the light...which I use. Hello...I'm a chick and I have to check, or do makeup in it some mornings.

The dealership selling the used H3 to me said, no, it would be a huge hassle and blah blah blah....but a service dept at another dealer said it can be done.

Has anyone heard of anyone doing this?

 

The electrical wiring of vanity mirrors on a Hummer and many other GM vehicles consist of two wires. One power wire and one ground wire.

The on/off switch for the mirror is activated and located on the flip-up door that covers the mirror when not in use.

Generally, what this means is that all you have to do is tap into a 12 volt constant-hot wire with the "power wire" coming from your mirror and tap into a Negative-Ground-wire with the Negative-Ground-wire coming from your mirror.

If I remember correctly, both the 12 volt "power wire" and the Negative Ground wire can be found under the trim on your "A" pillar.

If this is the case then, any additional length of wire you might need to run will only be a couple of feet long at most.

You mention that you are a female Hummer driver. Please pardon me if I sound like I'm patronizing you in any way but, if you've never done this type of install, my explanation may probably sound far more complicated than it really is.

All you'd really be doing is running the two wires from your vanity mirror to the two selected wires running down the "A" pillar of your Hummer.

The two wires coming from your vanity mirror are one white and one, black one. Black is your Ground wire and White is your Power wire.

Just remember; even if there is no white wire coming from the mirror, there is always a black wire.

This means that of the two wires, the black wire will always be the ground wire and the other wire (regardless of color) will be the power wire.

Hope this helps.
Upholstryguy