Service Trailer Brake System - 19 Denali

[dmax_ty]

Been fighting this dumb issue for a while. Replaced ITBC and trailer brake control module (above spare tire) to no avail. Fuses are all good, all I have accomplished is put a stop to the incessant dinging from the dash.

When towing, all lights work fine but zilch for the brakes. Could it be the plug? My V2 did not pull any codes.

 

[Mikey52]

I bought a #9107a electric brake force meter. That test the truck side. If truck is ok then it's in the trailer.

Is it EOH brakes or magnet style brakes on trailer?

 

[Ron Nielson]

Make sure fuses are good for starters

 

[dmax_ty]

Checked all fuses. I’m leaning towards the plug being bad.

 

[gassux]

if you're in the rust belt, check all of your grounds on the frame. Those straps start to disintegrate in a couple yrs. Check out south main auto on youtube, he had a similar issue with a newer gasser silverado and it was the ground. dealer wanted 3900 to repair and he put a solid ground strap in and fixed it.