Third brake light wire or CHMSL wire ???

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JohnnyB

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Well I finally got pulled over for never hooking up my 3rd brake light on the Leer cap I put on the sport trac. Now I am a week away from taking a long drive to another state for a little vacation for a few days and need to hook it up to avoid any future problems.

I have read on here about thrid brake light wire between the spare tire and the bumper ...... not there! I have been searching the internet for the elusive third brake like wire which is also known as the Center High Mount Stop Light. Explorer forum said it might be under the engine compartment fuse box. Small wire either capped or taped off not connected to anything. I believe is is supposed to be a green or light green wire. Any ideas of where this thing is???? Or am I stuck running a wire from the ST 3rd Bake Light to the cap 3rd brake light???

Help please ....... Thanks
 
Should be a light green wire, about 20 gauge, six inches long, and capped with a black insulator. Labelled CHMSL.
 
GEN 2 doesn't have this wire..... Dam ford !!! people have run wires from inside the truck third brake light and others from the 4 pin trailer connector. .. Sucks... Crappy design...
 
GEN 2 doesn't have this wire..... Dam ford !!! people have run wires from inside the truck third brake light and others from the 4 pin trailer connector. .. Sucks... Crappy design...

Yes that sucks big time. I ended up connecting to the 4 pin trailer harness but it flashes with the right directional. Ford dropped the ball on that one. Maybe some time I will have time to go all the way to the third brake light and do it right.
 
You may be able to pull the CHMSL and see what color wires are hooked to it's connector that then run down the C-Pillar, then splice into it under the door sill. Not sure if it runs down the C-Pillar or what side it may be on, just a thought.

On newer Ford pick-ups they provide extra terminals on the brake light switch located on or near the brake peddle. The company I work for installs caps and we are always looking for the CHMSL wire ;)
 
You may be able to pull the CHMSL and see what color wires are hooked to it's connector that then run down the C-Pillar, then splice into it under the door sill. Not sure if it runs down the C-Pillar or what side it may be on, just a thought.

On newer Ford pick-ups they provide extra terminals on the brake light switch located on or near the brake peddle. The company I work for installs caps and we are always looking for the CHMSL wire ;)

Thanks a good idea. I will try that out when I have some time. Thanks
 
I was having issues with trailer lights recently and when I stuck my head underneath, there is a spare/extra/backup 4-wire trailer plug under the bumper behind the rear facing 7 wire plug. Could you plug into that for brake lights?

That's an '07 with tow package.
 
You could but depending on which wire you tap into the 3rd brake light will flash with the directional.
 
There is a module that you can buy to stop the flashing brake while turn signal is on. Tap into either brake light, use the module, good to go.
 
Do you know what the module is called or where you can get it?
 
Like this.... AMAZON.....

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I was having issues with trailer lights recently and when I stuck my head underneath, there is a spare/extra/backup 4-wire trailer plug under the bumper behind the rear facing 7 wire plug. Could you plug into that for brake lights?

That's an '07 with tow package.
That's how I did it on my '08. Bought a trailer wiring harness and ran it behind the bumper up into the bed. Hook two of those wires together to make the brake light work. Brake light blinks with the left turn signal but it's not a big deal.
 
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