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Does anyone know a way to get to the brake switch output wire on a 99 suburban? I have stood on my head a stuck my hand evey where it would go above the stearing column but could not see it or feel it any where. Is there a place on the convenience center that would work. I'm installing an electric brake controller and need this wire to complete the project. If anyone can help I would love to hear from them.
 

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Does anyone know a way to get to the brake switch output wire on a 99 suburban? I have stood on my head a stuck my hand evey where it would go above the stearing column but could not see it or feel it any where. Is there a place on the convenience center that would work. I'm installing an electric brake controller and need this wire to complete the project. If anyone can help I would love to hear from them.
Is this what your looking for...by the brake pedal?

 

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Previous years the blue wire isn't under the dash. It is located in the engine
compartment along with the orange "hot" line. You'll find both these
wires taped to a wiring harness under the brake master cylinder. They
are very well taped making them difficult to find and even more
difficult to cut free for use. The orange wire will have a terminal
connector already on in. This is attached at the fuse block right
next to the master cylinder. If you remove the fuse blocks plastic
cover, you will see two studs sticking straight up. Put the eyelet at
the end of the orange wire over one of these studs and add a nut. The
nut will probably need to be metric to fit. The blue wire will have
to be run through the fire wall to be connected. You will have to
extend the wire to be long enough to reach the blue wire.

Also, be sure you run the power and ground wire for the brake
controller directly to the battery . Use a self resetting circuit
breaker on the positive side. Don't be tempted to run the ground wire
to something other than the battery as this will cause your brake
controller to perform poorly or not at all.
 

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Discussion Starter #4
Electric brake

Does anyone know a way to get to the brake switch output wire on a 99 suburban? I have stood on my head a stuck my hand evey where it would go above the stearing column but could not see it or feel it any where. Is there a place on the convenience center that would work. I'm installing an electric brake controller and need this wire to complete the project. If anyone can help I would love to hear from them.
Thanks for the info and it is helpful, but my problem is physically getting to the wire coming from the cold side of the brake light switch. The picture and discription is simple enough but the location of that switch is totally unaccessable as near as I can tell. I have the full GM shop manuels for this vehicle and have not been able to find the information I need. I suspect that there is a wire some where that is more accessable that can be tapped for that brake controller. If not I guess I'll have to take the dash apart to get to that wire.
 

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on my uncle's '99 1-ton dually (GMC btw, but that doesn't really matter), the person who installed the brake controller tapped into a wire that was about dead center under the steering wheel and right at the edge of the actual dash trim, so it was pretty much like 2 inches from where the person installed the brake controller. If you know what color the wire should be, you should be able to find the line in that loom of wires that runs through that part of the dash. Just test the line to make sure it only goes hot when you hit the brake ;)
 

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Thanks for the info and it is helpful, but my problem is physically getting to the wire coming from the cold side of the brake light switch. The picture and discription is simple enough but the location of that switch is totally unaccessable as near as I can tell. I have the full GM shop manuels for this vehicle and have not been able to find the information I need. I suspect that there is a wire some where that is more accessable that can be tapped for that brake controller. If not I guess I'll have to take the dash apart to get to that wire.
The brake line is actually easy to get at.
The switch actually pulls straight down the pedal shaft.

Crawl into your footwell, and put your hand on the brake pedal shaft. Slide your hand upwards until you find a plastic tab that wraps around the shaft. Grap that plastic piece, and pull straight down. This is the brake switch. It does not look like a normal plunger type switch. This is what throws most people off when they try to find it.
This is what the switch looks like when it's removed.
You can see where I tapped into my wire for my brake controller.

The question is going to probably come up, why did I splice into the white line? I have cruise, and splicing into the red gave undesirable results. For some reason when I would turn on the cruise control the trailer brakes would apply.

Sorry about the fuzzy pics. I guess my lens needs cleaning.
 

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Discussion Starter #7
Electric brake

on my uncle's '99 1-ton dually (GMC btw, but that doesn't really matter), the person who installed the brake controller tapped into a wire that was about dead center under the steering wheel and right at the edge of the actual dash trim, so it was pretty much like 2 inches from where the person installed the brake controller. If you know what color the wire should be, you should be able to find the line in that loom of wires that runs through that part of the dash. Just test the line to make sure it only goes hot when you hit the brake ;)
I found that connector in the book (c-266) and it said A1 is the brake switch output wire. I check it with a meter and confirmed the operation and we now have electric trailer brakes. Thank you so much for the help I could looked for days to find that info.
 

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Discussion Starter #8
Electric trailer brakes

The brake line is actually easy to get at.
The switch actually pulls straight down the pedal shaft.

Crawl into your footwell, and put your hand on the brake pedal shaft. Slide your hand upwards until you find a plastic tab that wraps around the shaft. Grap that plastic piece, and pull straight down. This is the brake switch. It does not look like a normal plunger type switch. This is what throws most people off when they try to find it.
This is what the switch looks like when it's removed.
You can see where I tapped into my wire for my brake controller.

The question is going to probably come up, why did I splice into the white line? I have cruise, and splicing into the red gave undesirable results. For some reason when I would turn on the cruise control the trailer brakes would apply.
Sorry about the fuzzy pics. I guess my lens needs cleaning.
Thanks for the help on the wire color, I found the switch but I didn't have the nerve to pull stright down. If I broke it I would never figure out how to fix it. Never the less you info did help and the brake is now working. Thanks for you help.
 
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