Brake Controller Wiring Expert Needed

[lilnotts]

I installed a Tekonsha P3 a couple years ago and it worked great until a few months ago. The display would no longer turn on and when I measure the voltage it was only 8.3V when the controller was plugged in(12V with controller disconnected). I called Tekonsha and they figured the controller was fried and sent me a new one for warranty. I tried installing the new one but the new one is giving me the exact same issue. To see if it was a bad controller I tried it on a seperate 12V power supply and it powers up just like it normally should and looks to be working fine. I tried using a small light on the same wires that feed the controller and it does the same thing when I plug in the controller, has 12V disconnected but only 8V with a load on it. Any idea what could be causing this issue?

[mike94silverado]

did you use the factory harness?

[mike94silverado]

Honestly, If it was me I'd just go to the RV store and get a universal kit to run all new wiring seems like that would be cheaper and easier than trying to sort out the factory system...

[hzhardy]

check the two nuts on your under hood fuse block. Also check your ground splice

[hzhardy]