How to wire a cap stop light on a 2009 silverado.

**rongrzywacz** · 10-16-2010, 04:02 PM

I have a 2wd 2009 Silverado, with towing package and Leer Cap. Does anyone know how to connect the brake light on the cap. I saw old posts that mention a chmsl wire, but i can't seem to find one. I would also like to wire up the dome light on the cap.

Thaanks for any help.

Ron G

**LikeARock47** · 10-16-2010, 04:24 PM

Not sure if newer trucks are the same, but:
On the old ones theres a white-ish wire in the trailer harness, thats the 3rd brake light wire. You may also have a constant power wire in there since you have towing package... that you could run to a switch and then to your dome light.

**rongrzywacz** · 10-20-2010, 09:06 AM

No white-ish wire in the Trailer harness..

**rongrzywacz** · 10-27-2010, 04:38 PM

ttt

**rt9bil** · 10-27-2010, 06:27 PM

Tap into the taillight/brake light and run a wires up through the stake whole pocket to the cap brake light. For the dome light I would tap into the power and ground wires from the licsense plate lights (theres only 2 wires) and wire it into a switch that you could hide up under the bed rail. This way the light will only come on when the key is in the acc position or the truck is running. If you really wanna get crazy buy a hood pin switch, mount it so when you open the tailgate the dome comes on. Just like when opening your doors.

**rongrzywacz** · 10-28-2010, 05:52 AM

I don't think that you can wire it to the brake lights, because the brake lights work with the turn signals. It would blink when you turned the turnsignals on.

**rt9bil** · 10-28-2010, 03:58 PM

If you pull off the tailight there should be several different bulbs. Unless GM went to LED or something. My '02 has seperate bulbs for turnsignal, brake light and reverse. Check it out.

**vlent19** · 11-07-2010, 06:21 PM

i use to install caps for are for yrs, you have to pull up the kick panel on the drivers side, in the wiring harness u will see a little pig tail stining out i cant recaall if itsw ble or greem, but like i said its a pig tail so u wont miss it, then dill a hole run the wire from there back to the cap under the truck, like u said the taillight and the brake light is on the same wire by the tail light. it sucks i hated doin caps on these trucks for thjat reason lol just so much work

**pmf608** · 11-07-2010, 10:09 PM

GM also used light blue wires for the CHMSL at the trailer harness, so look for one of those. Running a wire from the kick panel should be avoidable. On my '01, the canopy brake light is tapped into the left side brake light because it has seperate brake and turn bulbs, but that doesn't work on the 07+ with the brake and turn being the same bulb and wire. For my canopy dome light, it has a switch built into it. I rewired this switch to switch the ground instead of power, then ran a power wire from the battery. I ran a wire from the interior dome light ground to the canopy and tapped into that for the ground, as well as tapping into my brake light ground so that I can either use the switch or turn on the truck's dome light to turn on the dome light in the canopy.