CHMSL wiring in a truck cap/canopy/topper?

[great white]

Not sure where to post this, so this will have to do.

(we really should have a separate forum for the GMT400, etc)

I'm looking to wire up a CHMSL in my truck bed cap/topper/canopy/whatever you choose to call it.

Problem is, I can't see an easy way to wire it in without it flashing with the turn signals.

My options seem to be:

1. add a logic box, wire in with the brake/turn signals

2. run a dedicated wire back from the brake switch to the CHSML

Either way, not overly cheap or easy....

Are there any other options?

The ford boys have it easy, ford included a separate brake wire for just this type of thing.

I'm hoping Gm did the same, but after looking at some diagrams, I doubt it....

 

[bk95td]

I, for one, have no idea what a "CHSML" is:???: 3rd brake light?

 

[great white]

Center High Mount Stop Lamp (or light if you prefer).

I got the "hms" letters a bit mixed originally. Edited it to fix it.

Pretty much the same issue you would run in to when wiring a trailer....

 

[Chevylover]

Mine already got a wire incl. a fuse for a CHMSL on the driverside, coming up behind the driverside taillight and comes out inside the box, just below the rails.

Perhaps you should have a look there. If not, it shouldn't be so difficult to build by your own. Crab a testlight or got a wiring diagram(if you can wait till tomorrw, i will have a look in my manual, which colour the wire is), remove the driverside taillight and check, which wire is "hot", while somebody else is stepping on the brake. Attach a wire (we call it DC-thief here) to this hot wire, put an inline fuse and wire it up the the CHMSL. Don't forget the removeable connectors, if you want to remove the canopy, etc. sometimes.

Cu,
Sven

 

[great white]

Well, no luck with factory wiring. NADA, zip, zilch.

So, I ran my own wiring from front to back.

I tapped in under the dash for brake, and then tapped in for the dome light so it is activated through the cargo light. I also discovered the PO had wired the trailer brake controller wrong, tieing in to the wrong feeds under dash.

I drilled the brake booster holes in the firewall and gromitted them, used weather pac connectors so the cab can be removed if nesesary, split loomed/zip tied the harness all the way to the back, weather pac connectored the wires through a stake pocket in order to allow easy cap removal and tied/taped it all neat and tidy.

It's all soldered connetions and double wall weathertight shrink wrapped.


Looks nice and funtions like factory...

:thumbsup:

Thinking about fabbing up a rear wiper and washer now..........:hihi: