Brake Controller Troubleshooting in 2002 GMC Sierra Where Doesn't Work with Brake Pedal

Question:

My brake controller works manually with the push dial only and does not activate when the brakes are pushed in a 2002 gmc sierra I just installed it

asked by: Ruben A

Expert Reply:

It's very common your generation of GMC truck for the third brake light fuse to be blown and cause the brake controller not to work with the brake pedal. You can easily check this by pressing the brake pedal and seeing if the third brake light comes on or not. The fuse is commonly labelled CHMSL.

expert reply by: Jameson C