I have an Impulse brake controll on a 2005 chevy duramax, the trailer brakes work when I manually apply them. But the do not work with the brake pedal?
Year : 2005
Make : Chevrolet
Make (other) : Duramax
I assume that you wired this into the circuits that the factory provided for this under the dash?
I just used the harness or connection plug that came with the controller
Is there power on the red wire when you step on the brake pedal?
I don't think so.
OK. That's the input from the brake pedal. And you bought the harness that plugs into the relay center under the dash?
Right, I took this controll off my 2001 GMC (on which it worked fine) I now want to put it on my 2005 Duramax. It seem to remeber pulling a wire out of the harness on the GMC and hooking it up. Do i also need to do the same now?
The wiring may be taped up to the harness, or it may be prewired to the relay box. These are hit/miss for some reason. Here is a schematic, in this diagram they do say that the wires are blunt cut, so you should be able to find them easily under the dash.
ASE Master Technician, L1, Master GM Technician. Over 20 years of bumper to bumper GM experience.