Cab marker light wiring

Sour_Squirrel · March 20, 2018

OK I know there will be a lot of people that will hate what I’m going to do but I plan on installing cab marker lights on my 2017 GMC Sierra 1500.

I’ve always felt like it should be an option on the 1500 trucks as we do also pull trailers over 8’ in width.

Anyways I was wondering if anyone has done this?

I’m looking for information on where to take the power from to illuminate the lights. I don’t want to tap into the front side marker lights. I want to do a proper clean install. I’m sure there’s a spot somewhere on some wire harness I can tap into.

Help please....

wforrest08 · March 20, 2018

Jaychevy81 · March 20, 2018

Open the pass side fuse panel the is a spot where a plug would go can’t remember the number. You can clearly see it pin 3 left side is the marker light pin. If you order the factory harness it will plug right in no cutting splicing at all. I did this on my 2015.

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Likarok · March 21, 2018

I totally agree that this should be an option on 1500's. My 1/2 tons from the 70's and 80's had these on them and I have always thought they made a truck look like a truck! I do understand though that if you want a more sporty look, but exactly why the should be an option!

Sour_Squirrel · March 21, 2018

4 hours ago, Jaychevy81 said:

Open the pass side fuse panel the is a spot where a plug would go can’t remember the number. You can clearly see it pin 3 left side is the marker light pin. If you order the factory harness it will plug right in no cutting splicing at all. I did this on my 2015.

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Is there a factory harness just for the cab marker lights by themselves, or is it a harness with the cab marker lights with a bunch of other wires for other circuits?

wforrest08 · March 21, 2018

1 hour ago, Sour_Squirrel said:

Is there a factory harness just for the cab marker lights by themselves, or is it a harness with the cab marker lights with a bunch of other wires for other circuits?

https://www.ebay.com/itm/2015-Chevrolet-Silverado-GMC-Sierra-2500HD-3500-Cab-Light-Wiring-Harness-new-OEM/271871151702?epid=657073940&hash=item3f4cc88e56:g:IR0AAOSwtvtVVgMa:sc:USPSPriority!50236!US!-1&vxp=mtr

there’s a cheaper one listed different seller this listing has better pics. Looks like just the lights to me.

Kubs · March 21, 2018

Why is that harness 2015 specific? What changed between '14-'18?

I have lights from the '07-'13 style I never got around to installing on my old truck, and would like to add them to my '18 Silverado. Are the connectors on the light plug the same as the previous generation lights?

Donstar · March 21, 2018

I would also like to have these lights on my truck. Most of all I like the look but there is value in increasing your visibility on the road. After experiencing the shark fin leak issue, I'm a little shy about considering this modification in the future. However, if it was a factory option c/w warranty, it would be high on my priority list in a new purchase

Jaychevy81 · March 21, 2018

Is there a factory harness just for the cab marker lights by themselves, or is it a harness with the cab marker lights with a bunch of other wires for other circuits?

Yes there is a harness but there are several depending on options. Test the pass side fuse panel for that parking light pin. Mine did not have power so most of the harness was useless. You could easily make your own harness if you have to end up cutting that plug off and wiring it directly. I had to tap into the marker light door wire by the pass kick panel. I would have saved the 110$ if I tested this prior.

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Jaychevy81 · March 21, 2018

Why is that harness 2015 specific? What changed between '14-'18?

I have lights from the '07-'13 style I never got around to installing on my old truck, and would like to add them to my '18 Silverado. Are the connectors on the light plug the same as the previous generation lights?

When I was searching forums to do this Mod you can get a vin from a 2015 or other years with similar options that your truck has. Just cross reference part numbers should be the same. I stripped mine down because it had the GPS wire and a couple others I had already so I didn’t wanna dig and remove them. I wound up with 2 wires total wasn’t really worth it. You can make a harness and just harness tape it for a fraction.

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Kubs · March 21, 2018

24 minutes ago, Jaychevy81 said:

Yes there is a harness but there are several depending on options. Test the pass side fuse panel for that parking light pin. Mine did not have power so most of the harness was useless. You could easily make your own harness if you have to end up cutting that plug off and wiring it directly. I had to tap into the marker light door wire by the pass kick panel. I would have saved the 110$ if I tested this prior.

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Do you still have the plug you cut off by any chance? I could just order new pins for it and use that to make my harness. Long shot I know.

L86 All Terrain · March 21, 2018

I wouldn't punch a hole in it. A punch pulls and stretches the material that it is punching through just a little bit. High quality GM paint will loosen and eventually flake under and around the lights. I would recommend covering the area you want to drill in duct tape and drill the hole, remove the tape and you have a clean hole with no chipping paint. If you punch them in I would buy a can of touch up paint to clean it up after to prevent flaking. Would love to see some night photos when it is done.

Jaychevy81 · March 21, 2018

Do you still have the plug you cut off by any chance? I could just order new pins for it and use that to make my harness. Long shot I know.

I can check but I don’t think I do let me look.

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Jaychevy81 · March 21, 2018

I wouldn't punch a hole in it. A punch pulls and stretches the material that it is punching through just a little bit. High quality GM paint will loosen and eventually flake under and around the lights. I would recommend covering the area you want to drill in duct tape and drill the hole, remove the tape and you have a clean hole with no chipping paint. If you punch them in I would buy a can of touch up paint to clean it up after to prevent flaking. Would love to see some night photos when it is done.

Yea def don’t need a punch I went to staples and bought oak tag paper and made the 3 templates for the lights. I taped off the top of the truck with painters tape I taped the templates to the roof. Traced the 3 square holes out once I was set on measurements. Used a Dremel with the cut off wheel. Let me tell you cut through like butter minimal sparks.

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gkuklinski · March 22, 2018

Really want to add these to my 1500 as well, tow a lot and just plain looks good. However I am very nervous about cutting holes in the roof and possible future leaks. I like the Dremel idea, thanks for sharing Jaychevy81!