Improved Interior Lighting for a Monte Carlo SS with T-Tops

Lighted Rear View Mirror Modification
By Paul Carreiro, Updated September 3rd, 2002

Here's my first tip.. don't know if anyone has thought of this before.. it's easy, relatively inexpensive, and doesn't require a PHD in electronics. Please excuse the bandwidth.. I've added detailed instructions to help the electrically challenged among us.

The one thing I was disappointed in with my T-Toped 86SS is the lack of lighting in the driver/passenger area. The rear passenger lights are fine for the back seats.. and the low under-dash lights are great for tieing your shoes, but doesn't do you much good where you need it.. arm level in front.

One of the best things I've done to the SS is to replace my stock rear-view-mirror with a new LIGHTED one out of a late model Lumina/Monte Carlo. Mine is from a 92 Lumina and was ordered new from GM dealership parts. (GM Part Number 10078254) These have the built in lights that point down.. one each for the driver and front passenger.. each with a separate switch. (See photo above). At the time I performed this modification back in the early 90s, lighted rear view mirrors were a novelty, not common on cars, and certainly not commonly found in junkers at the bone yards. These days, you'll probably have good luck finding a used lighted rear view mirror from a donor. It certainly is cheaper than buying one new from GM like I had to.

GM has a lighted rear view mirror kit available. The part number is 12498112 and it includes a harness, all connectors required and instructions needed to install. GM list price is $75.00 for the kit.

Installation was a snap.. mechanically of course.. they all fit the standard mount. The screw used to secure the mirror to the window button has a Torx T-20 type head. You'll need a Torx T-20 screwdriver (available for a few bucks at your local autoparts store).

My concern about adding wiring up to the mirror was unfounded when I discovered that the wires for the rear inside lights passes up the left side of the windshield, across the front driver side top molding.. and straight back through he center bar.... passing the location of the mirror along the way.

The mirror should come with a 3 pin connector (commonly called a Molex connector in the electronics industry) with the pin out shown below:

/ o \ 12 Volts (Connect to Orange)
| o | Ground (new wire to ground)
| o | Switched Ground (Connect to White)

You will need to obtain a mating connector to this one.. with female pins. Take the mirror/connector to your local Radio Shack or electronics store to find a proper fit. They are rather common connectors in the electronics industry so should not be a problem finding them. (If you can't find them, contact me, I'll find em for you and send them). If you find an appropriate donor lighted mirror from a junk yard, make sure to also take as much of the wire harness (with mating connector) as possible.

Once you have the mating connector, solder 3 wires to the female pins. The center (ground) wire should be about 3 feet long, the two outer wires should be about 6 inches long. I used black ribbon cable to make it look good.


  1. Remove the drivers side T-Top
  2. Remove the 3 screws holding the drivers side visor
  3. Remove one remaining screw holding the top driver side molding
  4. Remove 4 screws holding the center T molding
  5. Remove the drivers side molding and center T molding

    You should see 3 wires.. Orange, White and Purple. Disregard the Purple wire if you have one (I believe it goes to the rear window defroster). The Orange wire is fused +12 Volts for the rear passenger lights (present 100% of the time). The White wire is switched ground for the rear passenger lights. This wire switches to ground when either door is opened, or you turn the light control fully counter-clockwise.. thereby completing the circuit path and turning on the rear passenger lights.

  6. Remove the stock mirror.
  7. Connect the mating connector to the mirror connector.
  8. Mount the new mirror on the window hub.
  9. Route the center (ground) wire from the new mirror to the left driver's T-Top mount. Unscrew the two T-Top mount screws.. slip the stripped ground wire underneath the mount.. and re tighten the screws. You may want to tape the ground wire up to the metal cross beam to keep it tidy.
  10. Using a wire "tap-in connector" (Radio Shack Part Number 64-3052), (These are the type that allow you to splice a second wire into an original without breaking it.) connect the Orange wire to the 12 volt wire from the mirror (refer to pin out above).

    Test #1: Switch each of the mirror's switches.. the lights should come on at this point. The rear passenger lights should be unaffected. Once verified.. turn each one off.

  11. Using another "tap-in connector", connect the White wire to the switched ground wire from the mirror (again, refer to the pin out above). Once you connect this connector (and assuming you now have the door open) both mirror lights should come on.

    Test #2: Close the car door. Verify that both mirror lights go out. Also verify the rear passenger lights go out. The mirror lights should match the state of the rear passenger lights. On with open door, Off with closed door. Once verified, close door.

    Test #3: Rotate the light control fully counter-clockwise and verify the mirror and rear passenger lights come on. Once verified, rotate the light control just past full counter-clockwise position to turn the lights off.

    Test #4: Repeat test #1 with doors closed. Once verified, congrats, it works!

  12. Dress wires with tape if necessary.
  13. Re-mount the center T molding and drivers side molding. Re-secure the drivers side visor. Replace drivers side T-Top.
  14. Dress wire(s) from the mirror to the molding so they look nice. Some modern cars now have a plastic molding that hide the wires between the headliner to the mirror. Look for these when you're at the junk yard.

Congrats! You're Done!!

I hope you find this as useful a mod as I have. You'll be amazed at the difference it makes! I also hope you found the instructions helpful.

I'd like to hear from those who implement this mod.. let me know what you think. If you have any questions, please route them to me via e-mail.. I'll try to help where I can (I'm fully electronics literate).

(Note: These instructions apply to the modifications I performed on my 86SS. Wire colors may differ from year to year. Also, you may not have the Purple wire if you do not have the rear window defrost option.)

(This tip may be added to any web "Tips / Mods" page provided prior notification to / approval from myself ; and of course, with proper credit given.)

Good Luck!

©Copyright 1999-2002,, All Rights Reserved