Wire location for Auto dimmer? [Archive] - GrandAmGT.com Forum


View Full Version : Wire location for Auto dimmer?

06-03-2005, 05:30 PM
Anyone know where this wire would be. I am talking about when you close your doors the dome and map lights automatically dim. I was thinking of hooking my LED circuit to it so the LED's Dim at the same time.

Any thoughts?

06-04-2005, 08:24 PM
anyone? I was thinking if I tap into the hot wire on the dome I should have the LEDs dim off too.

06-05-2005, 09:05 PM
anyone? I was thinking if I tap into the hot wire on the dome I should have the LEDs dim off too.

I tried that, there's 3 in my SE that lead to the dome light... no combonations worked on doing that. So, I ran my LED wires up to the domelight and attatched them right to the metal that the bulb sits in, which worked perfectly and it's what your looking for. I have 3 LED's behind each door reflector (12 total) and 3 in the cargo area under the HVAC control's wired up that way. It's been like that for a few weeks with no problems at all.

06-06-2005, 07:23 AM
The dome light does not work in the way that you would think. One wire is 12vdc all the time. One wire is the ground. The third wire is the one that changes from ground to 12vdc.

The bulb aways has 12vdc on the one side. The other side of the bulb is controlled by the switch. The switch has three positions, OFF, DOOR and ON. When the switch is OFF, the lamp is off. When the switch is in the ON position, the ground is connected to the bulb and the lamp is lit. When the switch is in the DOOR position, you get the theater lighting.

The theater lighting is strange. When the lamp is off, you have 12vdc on both sides of the bulb. The lamp comes on when the voltage drops from 12vdc down to ground potential.

How can you use this, you might ask? Find the wire that changes from 12vdc to ground and use that as your ground. Hook the other side of the LEDs to 12vdc through a switch and fuse.

It might be easier to hook the LEDs up like rickhigginshtbr did. That way you can control them using the dome light switch. No separate switch or fuse needed that way.

06-06-2005, 08:22 AM
Cool. Thanks, man. That was exactly what I was looking for. I'll keep you all posted.