Trailer Brake Controller Wiring Harness for a 2003 Chevy Silverado

Published 06/26/2008

Products Featured in This Question

Tekonsha Plug-In Wiring Adapter for Electric Brake Controllers - GM

(1200)

$21.00

Hook Probe Circuit Tester

(72)

$13.47

Question:

I have a 2003 Silverado 1500HD with towing package. I am replacing a bad brake controller Tekonsha with a Reese Brakeman Digital. I have a new wiring harness that I bought for my truck and have hooked up black to black, white to white, blue to blue, and red to red. When the manual button is activated, the trailer brakes works but when the truck brakes are pushed nothing happens. What did I do wrong?

asked by: Danny

Expert Reply:

It sounds as if you might have the wrong wiring adapter. The wiring adapter for the 2002 and 2003 Silverado will fit either vehicle, but the order in which the pins are wired is different. Therefore, if you have the incorrect one, it will still plug in, but will not work correctly. For the 2003, you would need part # 3015-P, not the 3025-P which is for the 2002.

This can easily be verified by using a circuit tester like part # PTW2993 on the red wire exiting the rear of the controller. If the wire does not show any voltage when the brake pedal is pressed, you most likely are using the wrong adapter.

If this is not the case, and you indeed have the correct adapter, take a look in the power distribution box under the hood. Look at the diagram on the lid and find the location of the CHMSL fuse. Check this fuse and replace if necessary. If this does not solve the problem, get back with me and we will explore some other options.

expert reply by: Mike L