Originally Posted by mrader88

hopefully someone can help me, i got a light from the dealer but it only has the single large light not the two smaller "map" lights, i attempted to do the wiring the same but cant get it to light up, does any one know where i need to solder the wires to make this work? thanks in advance.

Originally Posted by YelloEye

Glad to hear you figured it out and saw the light.

Originally Posted by silver cobalt SS

I tried this but with led light strips...but..I wired the lights to the wires the + to the gray wire the - to the black wire and when the mirror lights was on the wire up in the roof by the sunroof didnt have pwr but when the mirror lights went out the wires would have pwr...then when I opened the door the pwr would leave as soon as the mirror lights came back on... I was connected to the gray wire..for + lead with door open

So I didnt install anything....

My cobalt is a 06 are the wires differant in an 06, or does anyone know what I did wrong? thanks

Originally Posted by mrader88

My understanding is there is a constant power (blue with white line) and the black and gray are two seperate grounds, black all the time and gray with the door. So if u want the led to turn on and off with the door run the blue to ur positive and gray to negative

Originally Posted by NCC-2000

Alright, most people who own a Cobalt (or G5) with a sunroof have at one point or another cursed the fact that these vehicles do not have an interior dome light, instead having only the small map lights in the rear view mirror. In this guide, I'll show you how to install a factory dome light in a vehicle that has a sunroof and have it look like it was always there.

What you'll need:

1 Dome Light Housing Part#22736100
1 Dome Light Lens Assembly Part#22736098
2 Bolts with nuts and lock washers (I used 1/4" bolts 3/4" in length)
10 1/4" rubber washers
3 Quick wire taps
Some wire
Wire strippers
Soldering iron & solder
Sharp Instrument For Cutting
Drill
Writing Utensil
Electrical Tape
Anything else you think you may need to complete this

Step 1:
Since you're dealing with electricity, probably wise to disconnect the battery. No major risk here, but you never know. After that, remove the rubber trim from around the sunroof.


Step 2:
Pull the headliner down a bit and take a look at this large metal brace with two holes in it. This is what the dome light will eventually be mounted to.


Step 3:
Pull the headliner down a bit where the sunroof switch is located and find the wire harness that leads to the rear view mirror. There are three wires in this, Black, Gray, and Blue.


Step 4:
Follow this wire harness as the wires join up with the rest of the wires up in there and follow it around the sunroof's left side. You will be tapping into these wires to make your dome light work. You can tap into them anywhere along their length, I just used the left side of the sunroof because it's the easiest way to access them.


Step 5:
Prepare your dome light parts. On the left is the housing, on the right is the lens assembly.


Step 6:
Grab the wire you will be using and strip one end of each. If you have the same colors of wire it will greatly reduce confusion, black, gray, and blue. Solder the blue wire to the rightmost terminal in the dome light housing. This has what looks like a small fork sticking up through it. Solder the black wire to the other terminal with the fork thingy, which is the leftmost terminal. The gray wire must be connected to the terminal beside the black wire, either on top or in the location where the plug would normally go. I chose to solder mine where the plug goes so that I kept all the solder locations away from each other, also helps give you more maneuvering room. There are four pins in the plug area, the gray wire goes on the second from the left if you're viewing the housing from the top (light bulb) side.


Step 7:
Mark the location of the holes in the metal brace onto the housing. The holes are roughly 5.5cm apart, which correspond to the spots just outside the little plastic "dividers" in the housing. Drill two holes in the housing to match these holes in the brace.


Step 8:
Do the same for the headliner, mark the holes so you know where they are.


Step 9:
Hold the housing up to the headliner, matching up the holes. Trace a rough outline of the main area of the housing.


Step 10:
Cut out the hole.


Step 11:
This step is optional, but highly recommended. Take the housing and turn it over. Cover up the area with wires with electrical tape or other covering of your choice. The idea here is to eliminate the chances of a short circuit forming and you blowing fuses.


Step 12:
Connect the wires from the housing to the wires running along the side of the sunroof. I used the quick taps for simplicity, feel free to use whatever you're comfortable with.


Step 13 (updated):
Place a rubber washer on each bolt, then feed your bolts through the holes in the metal brace. Once through, place two more rubber washers on each bolt, then feed the bolts through the housing. Place two more rubber washers on each bolt and secure everything using lock washers and nuts. If your bolts are too long the switch in the dome light won't operate as it should, so test it out now to see if it slides all the way in both directions. I added rubber washers to this step because it virtually eliminates the chances of a short developing and blowing the interior light fuse.


Step 14:
The lens assembly locks onto the housing using four tabs. Make sure the headliner isn't in the way. If it is, cut more of it off until everything is clear. Once done, take the lens assembly and push it onto the housing. You will very likely have to push down from the top in order to do this, as it's quite a tight fit. You'll hear (and feel) a click when the tabs interlock. Once all four tabs are locked in, you're finished. Clean up the mess you made cutting apart the headliner, reconnect the battery, replace the trim around the sunroof, and try your new dome light out. You'll appreciate it more once it gets dark.



Congratulations, you just made the interior a lot brighter. One small thing to take not of. I installed my dome light with the large light facing forward, and the two smaller lights facing back. You may choose to install it the other way. It's all a matter of personal preference. Enjoy!

UPDATE: I've installed LED bulbs in both the mirror lights and the dome light, so I figured I'd try to show the difference between having the dome light installed and the stock way.

Here's the LEDs during the day:



Now at night. I've retaken these photos with the car parked in my garage with all the lights off. This is the absolute best way to show the difference in illumination in photos that I can come up with, so I hope they get the point across.

This is just the map lights on the rear view mirror lit:

This is the mirror lights plus the main (or front half) of the dome light:

This is the mirror lights, the main dome light, as well as the map lights on the rear half of the dome light:


Hope that shows how GM screwed everybody that got a sunroof by not putting the dome light in from the start.