2009 GMC 2500 with ITBC/Classic disc brakes
I have previously posted my problem, but since I have worked it through to a solution I am starting a new thread.
Situation: I recently purchased a 2009 GMC Yukon XL 2500 with the factory Integrated Trailer Brake Controller (ITBC). My tow is a 2007 Airstream 27 FB Classic with electric/hydraulic disc brakes. Upon initial hook-up, the factory controller did not recognize or function with the Airstream. I had no brakes.
First Try: I went to the GMC dealer with my problem and their diagnosis was that my ITBC was not hooked up. They stated that they "hooked it up." (Incorrectly as I later discovered.) Back to the Airstream and the ITBC still did not function.
Second Try: After searching the internet I became convinced that if I really "dug deep," I would find a trailer harness stubbed off way deep under the dash to the left of the steering column. A few skinned knuckles later and I dug out the harness! It is a 4 wire to 4 wire hookup to the Prodigy controller and not difficult.
GM wire Prodigy Wire Function
red/black black battery power
white white ground
light blue/white red brake light signal
dark blue see 3rd try brake signal
Third Try: I initialy hooked up GMC blue to Prodigy blue. Then I became concerned that I might have 2 controllers on line trying to control the Airstream brakes. I called the Prodigy customer support number (1-888-785-5832) and talked to Danny Dunn. He informed me that would indeed be the case. He told me that I should not connect the Prodigy blue to the GMC harness blue, but that I needed to "ignore" the GMC harness blue and run a new 12 ga. blue wire from the Prodigy blue back to the connector at the hitch. He emailed me detailed instructions. My compliments to Prodigy and to Mr. Dunn for their outstanding product support. One more hint: I found a convenient place to go through the floor under the floor mat where the emergency brake goes through. I pierced the grommet with a sharp awl and pushed the 12 ga. blue wire through for a weather tight seal.
Sucess: After following the procedure emailed from Prodigy, I hooked up, followed the calibration procedure and now have a smoothly operating brake system.
Postlude: There are 2 power wires to hook up under the hood at 2 posts on the fuse box (one small and one larger). The dealer had mistakenly hooked both wires to the smaller post.