Troubleshooting Draw-Tite Activator ll Brake Controller On 2002 GMC Sierra

Published 02/06/2015

Question:

Hi guys, I have a draw tite activator 2 brake controller and it has flawless the past few year! I do have an issue with it now though. First off, when I am driving my truck 2002 sierra 2500 without a trailer hooked up my decimals 0.0 flicker like there is grounding issue involved or something. then when i use my right turn signal and apply the brake to turn the 0.0 blinks with the turn signal. so that is my first issue. My second is when i am connected to a trailer. The trailer brakes work great with no issue, but the running lights dont work what so ever until i apply my brake then the running lights and trailer lights turn on. if i just use the 4 ways or the turn signals they work but not until i apply the brake the running lights will go on. So i dont know if its a wiring issue, grounding issue or a controller issue. Im hoping to go the right direction to fix this issue. P.S. the trailer lights do work great on other vehicles so i know its not just the trailer, it happens on all of them. Thanks!

asked by: Kaj C

Expert Reply:

Since you said the trailer lights work great on other vehicles that helps narrow down the probable cause of the problems you are having.

There is some testing you can do. In the truck cab you will need to sever the blue wire several inches from the back of the controller. Then use a circuit tester like part # PTW2993 to test the end of the blue wire coming out of the controller. It should only have power when you apply the manual override or brake pedal. If it shows power at idle, then there is something wrong with the controller and it will need to be replaced.

If it tests fine, then reconnect the blue wire. Then move to the truck side trailer connector. Many times, dirt or corrosion can cause a short in a trailer connector. Make sure the truck and the trailer side connectors are clean and free of corrosion inside and out.

You can test the brake output pin and it should only show power with the manual override. If it shows power any other time, then there is a short somewhere between the connector and the brake controller you will need to track down.

expert reply by: Jeffrey L