drfife wrote:
I have a 2012 GMC 3500HD with integrated trailer brake controller and tow a 5th wheel with disc brakes.
The GM ITBC will not function properly without brake magnets in the circuit.
It's a simple fix.
Here's a PDF from Excel with diagram of how to set it up. Scroll down to see the info you need in the PDF.
http://www.excelrvs.com/assets/files/service-bulletins/GMC_Integrated_Brake_Controller-SERVICE_BULLETIN.pdf
We have 2011 Chevy and wired the magnets in....works Perfectly! Tells the controller a trailer is attached...