Chevy with brake controller problem.

sbodi4d wrote:
Went to pick up my new Pup at the dealer yesterday, but they could not get the brake controller to work on my truck for some reason. I have a 2007 Chevy Silverado 1/2 ton new body style. I think they said they had power to the controller, but nothing back at the seven way plug. They told me there must be something wrong with the factory wiring harness, and to take it to a Chevy dealer to get it checked out. He said it would flicker on, but not stay on, so he thinks the controller is good, but I think it may be a bad controller. All I know right now is it is a Tekonsha controller. Not sure what model or anything, but they charged me $175.00 for the controller with installation.
Anybody had trouble hooking up a brake controller to a Chevy? The only thing on the truck that isn't factory is a Leer camper top that I had installed two or three years ago. The high mount brake light on the camper top doesn't work some times, but it works most of the time. The inside light for the camper top has never worked, but I was going to look at it sometime to see why. I don't think that has anything to do with the brake controller, but I have seen some strange electrical stuff before. Any input would be appreciated.

The red flag for me is the intermittent high brake light (CHMSL). That runs off the same feed from the brake switch as is used to drive the brake controller.
Are the regular brake lights working OK? The feed from them is split from the turn signal switch AFTER the CHMSL feed is taken off.
If the brake light feed is intermittent, so will the brake controller be.
A brake controller is not rocket science! The dealer tech should have been able to figure it out!

There are four wires:
- 12V power
- Ground
- signal from the brake switch
- output to the brakes

I would start by checking for the 12V power and then 12V signal from the brake switch. If this signal is intermittent, then so will the brakes be.
If these check out, check the ground and then continuity of the output wire back to the 7-pin at the back of the truck.
If this all checks out too, then, unless the controller is defective, you WILL get a brake signal at the 7-pin, but as someone else said, you do need some kind of a load back there for the controller to work.
Ideally, plug in the trailer and listen for the magnets clicking or humming, else wire a couple of stop lamp bulbs in parallel to ground to present a 3-4 amp load to the controller.