# Chevy/gmc roof light connection w/ plow prep package



## BMWSTUD25 (Aug 21, 2008)

Hey guys, Just looking for a little help. I have a 2004 GMC with a plow prep package which means I have the switch on my console already mounted for use with a roof mounted light. I want to run some more lights on my truck and was sure this connection is made through the third brake light but when I took off the light and looked in I couldnt see any wires. Any help or hints would be greatly appreciated.


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## Schwinn68 (Jan 7, 2009)

the wires are under the headliner on the drivers side


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## BMWSTUD25 (Aug 21, 2008)

Awesome....now just one question, how do I get to them and pull them out and what will I see to know I found it? Just one hot wire im assuming??? Thanks again man


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## Kodiakguy (Sep 11, 2009)

Where is the switch located on the consol. Overhead consol? Ive got an 09. The switch, relay are overhead. the wiring is tucked under the headliner near the relay. Mine had a green wire and black wire. Black is ground, green positive. There was also a fuse up there w the relay. Check them with a meter to make sure and test the switch. I removed my 3rd break light, and fished the wire to the breaklight. I used a 2 pole trailer wire connector to attach it to my lightbar. I ran the wire under the breaklight to the outside of the truck and put the breaklight back in. as long as the wire comes out under the breaklight the weatherstrip on the breaklight will still seal, or you can use a lil silicone. oh, the max amp draw from that relay is 30 amps, dont try to wire anything to the switch itself, the switch will overload and burn up.


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## Kodiakguy (Sep 11, 2009)

the counsol is prob held up with at least 2 screws. prob under a maplight or something. if you dont have a fishtape, use a wire coat hanger, tape the end of it good so you dont scratch the paint under the headliner, it will trap moisture and eventualy rust. once you get whatever ur using to fish the wire to the wire. use electrical tape to attach it to the fish tape/coathanger and pull it through. sometimes it helps to have a second set of hands feeding the wire. the wires should be taped together


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## got-h2o (Sep 26, 2008)

The wires are where Schwinn said. I find it easiest to remove the drivers side rear pillar cover as that's where the harness feeds from. IIRC its a purple wire. It's best to locate the harness and start probing with a test light. Its obviously only hot one when the switch is turned on. Bear in mind it's on a relay, so trying to get feed power near the switch is not an option.


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## Q101ATFD (Oct 24, 2006)

The relay for the wires is behind the belt tensioner for the drivers side seatbelt on the rearmost pillar under the plastic trim. The wires (brown and black) go straight up the pillar and to the previously described location between the roof and headliner. Tap into the lines anywhere from the relay to the ends.


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## nbannan (Aug 26, 2009)

I just had my center console out so I can tell you it is 2 spline drive screws to take the overhead console down. Just gently pry the clear plastic light cover down (I used a jacknife blade edge) from the edge closest to the rear window. The 2 screws are near the Lights.
My wires were taped up & stuffed in the cavity above the lights. Green & Black as described by KodiakGuy. I also needed power for backup & hitch cameras. I found a wire in the green connector near the brake pedal (Under the Plastic cover) that gets juice only with the key on (low power draw only) Just an FYI as most of the Pink & White wires are Hot to the battery at all times & I didn't want to kill the battery accidentally.


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## Kodiakguy (Sep 11, 2009)

just be careful you dont tap into any wiring for the body control computer. it sends signals digitaly in varying positive and negitave voltages. if you grounded it or put 12 positive to it somehow you will fry the computer


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## BMWSTUD25 (Aug 21, 2008)

Thanks again for all the replies.....I still may end up just running them into my switch box. Just thought if the wires were right there behind the brake light waiting it would be an easy add on. its just to add some more clear lights for backing up.


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