Trailer Brake Controller Installation - 2008 GMC Sierra - etrailer.com

[revrend2]

The blue wire from the harness has constant power, and doesnt work. The red wire from teh controller has to go to the Orange wire from the harness in order for the Trailer brakes to work.

[etrailertv]

@revrend2 The orange wire on new GM trucks is an illumination wire and should not be used for a modern brake controller install.

Vehicle-Controller

Red - Black

Dark Blue - Blue

Light Blue - Red

White - White

We have a wiring FAQ that may be helpful. If you visit etrailer(dot)com and under the 'Help Info' tab, click on 'Help Articles', then 'Brake Controller', there is an article on the install of a brake controller on a GMC or a Chevy. Let me know if you have any more questions.

[revrend2]

@revrend2 well, when we hooked the trailer brake up following this exact video, they were on constantly, and didnt figure it out until last week. When we changed the wire, it worked fine.

[khtruckn]

nice, thank's for the info.