07 Sierra - Park Lights on with Brakes Applied

[gak1313]

Hello
The vehicle is a 07 SIERRA CLASSIC Crew Cab short bed made for Canada.
(Z49) It is a 4 sp, 6.0L, rated at 9200 GVW.

I am using a Tekonsha Prodigy brake controller for towing. (it came out of my 02 Yukon-worked fine) The contoller powers up ok with the truck's B+ and ground.

I discovered that the output wire from the stop lamp switch (ckt 1620) is not present at the C1 connector F9 pin of the i/p relay center. Installing a jumper to the output white wire (ckt 17) of the stamp lamp switch enabled the controller to work. Now when I depress the brake pedal all running lights will illuminate. IF the stoplamp circuit to the contrller is opened, all lights work fine except there is no brake output from the brake controller to the Blue wire for the trailer elec brakes. The Blue wire for the trailer elec brakes is not shorted to any other circuit in the truck. (ohmed it to all pins in the C1 connector)

Just recently bought the truck used, thus i DO NOT know it prior history.
Ideas???

 

[happy 2011]

well to me i would say you need to know if it's tk or trailer. So this is what i would do i would not plug the trailer plug in but i would jumper the green wire and yellow wire of the trailer to the tk.

Then have someone step on the brake and see if there is power in the brown wire on the trailer side.(use a test light) If there is then the problem is trailer side if not tk side.
If no power on trailer side check tk side.

Hope this helps

 

[gak1313]

fixed

Before I did what you offered, I double checked the 7 way rv connector, sure enough with NO trailer connected, with brakes applied, there is 12 volt on the brown wire for the running lights. h'mmm back to the brake controller factory harness, since I had to make a jumper for the brake controller to work, maybe the pin that should have been in the brake switch input was in this truck a pin that was connected to the running lights. I removed the Tekonsha factory wire only at this pin and the runnning lights were no longer powered up. after 5 hours it is fixed.

Thanks for another point of view....