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mwiener2 11-28-2005 12:31 AM

Map Lights on with Dome light Mod
(12/27/2011)EDIT: Apparently some people have done stuff wrong and fried their BIU. Be warned.

This mod makes the Map lights come on and then dim off with the dome light when the doors are opened or the car is unlocked. The map lights still work independantly like they did before. The dome light can still be completely turned off but the map lights will always come on with the doors and unlocking reguardless of the dome light switch.

As with all my walkthroughs, you should have basic electrical knowledge and understand how to pull apart and put back together your car. I'm not gonna hold your hand through all the steps, just the hard ones.

1. Remove dome light by popping off the cover and unscrewing the two screws.
2. Tap the middle wire in the loom. It's the brown and white one. I recomend using a multi-meter just to be sure though.

3. Remove map light assembly.
4. On models with a sunroof, pull off the plastic trim around the opening and thread your wire in there. On models without a sunroof, fish the wire from the dome light opening to the map light opening.

5. Get the wire and plug that power the map lights. Cut back the insulation to expose the wires.

mwiener2 11-28-2005 12:40 AM

6. Now this sounds odd, but just do it. Reverse the wires.

7. Now get some diodes. And wire one to each side of the bulb side of the map light button. Direction of diode is important. Make sure it works before you seal everything up. Be very careful here. The first time I did this mod, I put too much heat on the button and it melted stuck. The trick is to get a nice hot glob of solder on the iron and get it to stick fast.

8. Tidy up.

I'd check everything with a meter before starting to cut wires or anything, just cause who know what differences there are between models. The map light buttons are very sensative to heat, becareful, they'll toast.

03Indigo 11-28-2005 12:57 AM

Nice. This will be the first major mod once I move into the new house...and can find all my tools and soldering stuff.

great pics and write up. Thanks.

mwiener2 11-28-2005 01:05 AM

I did this on my OBXT months and months ago. But I did it half assed. I tried to do it without Diodes, simply casue i didn't have any at that moment. Needless to say, the map lights did come on with the dome light, but if you turned on either map light, both map lights and the dome light also came on. When I went back and added the diodes, I toasted the map light buttons. Then I spent about 3 hours rebuilding the inards of the buttons....they're really really tiny. So this was round 2 on dad's LLbeanie and I got it right first try.

03Indigo 11-28-2005 01:28 AM

what are the specs on your diodes? So I can keep that in a file for February, when I have a garage again.

mwiener2 11-28-2005 10:13 AM

um, just go to radio shack and get some moderatly sized ones. Most of them are rated 120v for 30watts or something, so on a car they're good for alot more than 30watts at 12v. I think the largest diodes at radio shack are only $3 for a pack of two. I'll see if I can find the package with the specs on it.

mwiener2 12-03-2005 11:52 AM

I forgot to look at the package and it's long gone by now. The people at radio shack should be able to help you pick one out when you tell them what your doing. Just say these key words: 12 volt DC system, about 100 watts.

PeterJMC 12-04-2005 03:05 PM

I did this mod today, the front of the cabin is nice and bright now! These is a great walk through, thanks mwierner2!

Iit took me a long time to finnaly get it finished, I think it was about 2 hours total. You can deffinetly do this under 45 minutes if you know what you are doing. It's mostly because I had to redo my solder connections acouple dozen times, and run back and forth to test things before made it nice and pretty.

This is the Diode I used from Radio Shack,

You can actually tap into the brown wire from the dome light up front by the map lights. The dome light wiring harness is just left of the map light inside the headliner. I ended up taping into the brown wire like mwierner2 suggested, I didn't realize the wiring harness upfront until later.

mwiener2 12-04-2005 03:12 PM

so the wires for the Dome light run by the map light area. Doh!

PeterJMC 12-04-2005 03:19 PM

Yea, Doh!

Ohh yea, when installing the Diodes since they are directional... the gray band on the diode should be away from the map light button. I hope that made sense.

SPEC-B-4-ME 12-08-2005 06:08 PM

:eek:Why do you have to reverse the wires? Any other way without cutting the original wiring? If I have any warranty issues with electrical stuff in the future, the dealership will say it is because I altered the original wiring.:icon_sad:

[quote=mwiener2]6. Now this sounds odd, but just do it. Reverse the wires.

mwiener2 12-08-2005 06:15 PM

By doing any part of this mod you're gonna get scrwed in the warranty. The reason for switching the wires is to move the ground to the other side of the switch. It won't work any other way....unless you switch some wires on the dome light side.

KTA156 01-10-2006 03:38 AM

I am writing to you guys from Singapore. What you guys do there constantly amazes me. I followed you clearly laid out instructions and managed to get it to work!

While working on it, I realised a few possibilities, so here goes:
I managed to remove the pins from the power connector at the map side,by lifting one end of the plastic connector (there is actually a break in between) and swopping over the leads. However, please be careful not to snap the connector or worse yet short the leads as there is 12v constantly present there.

In my car, unfortunately the wring harness to the dome light does not run thru the map lights area - so I would advice one and all to check before cutting the wires to length!

Also, I think smaller diodes will do the trick like 1N4007 ( cheap!). Once again, thanks a million!

PeterJMC 01-10-2006 07:42 AM

Glad it worked out for you. It's a smiple mod and mwiener2 did a great job with the instructions.

For those who haven't done this mod... DO IT! Huge difference at night time, the whole cabin lights up instead of just the rear seatting area.

crash 01-19-2006 02:36 PM


Originally Posted by peterjmc
You can actually tap into the brown wire from the dome light up front by the map lights. The dome light wiring harness is just left of the map light inside the headliner. I ended up taping into the brown wire like mwierner2 suggested, I didn't realize the wiring harness upfront until later.

Has anyone actually tapped into this wire yet (the rear dome wire that runs by the front map lights)?

I was looking at this last night and I couldn't find those wires. It appears to me that there are a few wires that run over to the vanity mirror lights for the passenger, but none that run back to the dome light.

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