Integrated brake controller

[rp709]

I bought a 2008 GMC Sierra Duramax to tow my 2005 Airstream. The GMC has an integrated brake controller and it doesn't work with the electro-hydraulic Airstream brakes! I'm told I have to use my Prodigy controller. The problem is that GMC runs a stubbed off wiring harness under the dash that has now power. How do I activate this harness?? The owner's manual only says the wiring harness is not hooked up and you have to deactivate the factor controller to use an aftermarket. Thanks.

[rtaylor537]

This is surreal !!!!!!!!! I no more than finished my question and one minute earlier you made the same inquiry. However, I had heard that the GM integrated unit was not compatible; one small reason I chose Ford.
But if it is the ActivBrake unit call Mike at the company and he will describe how to make necessary corrections.

[HowieE]

I would go to the dealer and ask to see the wiring diagram for the controller. GM draws their diagrams per subassembly, door locks, headlights ect. While they are a bit hard to deal with if you are working with more than one circuit you are just interseted in on circuit and a fairly straight forward one at that.

[biggoofball]

I just bought a GMC and scheduled an install of my drawtite prodigy type controller. I haven't taken delivery yet but after reading the specs I thought it was a simple. According to my trailer guy it's not easy. He has to hard wire it just like my 96 Buick.

[peegreen]

Originally Posted by rpcarlson

I bought a 2008 GMC Sierra Duramax to tow my 2005 Airstream. The GMC has an integrated brake controller and it doesn't work with the electro-hydraulic Airstream brakes! I'm told I have to use my Prodigy controller. The problem is that GMC runs a stubbed off wiring harness under the dash that has now power. How do I activate this harness?? The owner's manual only says the wiring harness is not hooked up and you have to deactivate the factor controller to use an aftermarket. Thanks.

I understand there is a work around; something like installing a magnet near the brakes to trick the system. Friends of ours have the Duramax with IBC and the their hydraulic brakes did not originally work until they got this info from the brake manufacturer and now this solution works.

[peegreen]

Originally Posted by thatismytruc

I just bought a GMC and scheduled an install of my drawtite prodigy type controller. I haven't taken delivery yet but after reading the specs I thought it was a simple. According to my trailer guy it's not easy. He has to hard wire it just like my 96 Buick.

I'm finding this hard to believe because Tekonsha, the maker of Prodigy, sells a harness for GM, Ford and Dodge to connect the unit to a plug under the dash - simple as plug n play. Used it on my Ford, friend just bought a Dodge and used the harness there and I've seen in catalogues the harness for GM. See below for random supplier.

Tekonsha® Brake Control Wire Harness - 1

[biggoofball]

That link does not give an option of picking a 2008 harness.

[rp709]

The point is not the harness. The problem is the GM does not connect there aftermarket harness to power if there is a IBC. There is a connecting wire taped to the fender by the drivers side fuse box. The question is what stud does this go to and which wire is disconnected to disable the IBC. GMC says that you need to disconnect the IBC, they just don't tell you how to do that and enable the wiring harness.

[moymew]

Originally Posted by rp709

The point is not the harness. The problem is the GM does not connect there aftermarket harness to power if there is a IBC. There is a connecting wire taped to the fender by the drivers side fuse box. The question is what stud does this go to and which wire is disconnected to disable the IBC. GMC says that you need to disconnect the IBC, they just don't tell you how to do that and enable the wiring harness.

Guys,
I had same problem. If you can't get the wiring harness... here is the Chevy Tech Bulletin on how to wire into electrical bus for after market brake controller for 2007/2008 GMC Sierra and Silverado.

2007 brake controller

[peegreen]

Originally Posted by thatismytruc

That link does not give an option of picking a 2008 harness.

I wouldn't give up - maybe this site hasn't been up dated - go directly to Tekonsha.

Tekonsha

[biggoofball]

Gmt900 Electric Trailer Brake Controller Install - GM-Trucks.com

It's a complete how to. very well written. I got it from this site:

GM-Trucks.com

[biggoofball]

just noticed that this is what MOYMEW posted. sorry.





Subject:
Procedure For Installation of Aftermarket Trailer Brake Controller in Lieu of Factory Installed Integrated Trailer Brake Controller #07-08-45-001A - (09/07/2007)

Models:
2007-2008 Chevrolet Silverado





2007-2008 GMC Sierra





with Integrated Trailer Brake Controller (RPO JL1)

This bulletin is being revised to add the 2008 model year, additional installation information and to emphasize that this is not a warranty repair. Please discard Corporate Bulletin Number 07-08-45-001 (Section 08 -- Body & Accessories).


Some vehicle owners may request to have an aftermarket trailer brake controller added, in lieu of the factory Integrated Trailer Brake Controller (ITBC) RPO JL1. This request may be made if the trailer being towed is equipped with electric over hydraulic brakes. This style of trailer brake system is not supported by the ITBC. An aftermarket trailer brake controller may be installed to operate with the electric over hydraulic brakes, however the factory installed ITBC system will be disabled.
Installation Instructions
To install an aftermarket trailer brake controller, use the four blunt cut wires located near the data link connector. Make the following changes to the vehicle harness:




Four Blunt Cut Wires


Dark Blue

Circuit 47

Brake Signal to Trailer Connector


Red/Black

Circuit 242

Battery Power


Light Blue/White

Circuit 6311

Brake Switch Input


White

Circuit 22

Ground

1. The Red/Black wire, circuit 242, must be connected to stud #2 of the 30 Amp fuse of the Underhood Fuse Block. This wire is located between the left fender and the Underhood Fuse Block.
   Locate connector X126 (on vehicles with RPO JF3 or JF7) or X115 (on vehicles with JL4) near the Underhood Fuse Block (Refer to SI Document ID# 1849049). Circuit 47 from the blunt cut wires near the data link connector will end at connector X126 terminal "G" or X115 terminal "B5." Obtain enough Dark Blue 12 gauge wire to run from X126/X115 to the 7-way trailer connector at the bumper. On one end of the Dark Blue wire attach terminal part number 15304732, located in Delphi Tray 8 and insert into X126 "G" or terminal part number 15304720 located in Delphi Tray 19 and insert into X115 "B5." Run the Dark Blue wire in its own conduit along the frame to the 7-way trailer connector at the bumper. Remove circuit 47 from the 7-way trailer connector terminal "C" and tape the bare terminal and attach to the harness. Attach terminal part number 12110853, located in Delphi Tray 4, to the other end of the Dark Blue wire and insert it into the 7-way trailer connector terminal "C".

Important: This procedure will not result in any Trailer Brake related display messages to be set. However, ITBC diagnostics will continue to function. If an ITBC fault is detected, a "Service Trailer Brake System" message will be displayed on the Driver Information Center (DIC) and an appropriate DTC will be stored in the ITBC module. The operator will still be able to adjust gain and access the "Trailer Gain / Output" display page in the DIC. However, the factory installed ITBC system will not sense a trailer connection and will not provide output to the trailer.
Warranty Information
This installation procedure is to be performed at the customer's request and at their expense. It is not a warranty repair and a claim should not be submitted for reimbursement.

[biggoofball]

Picked up the new TV, and brought it straight to my hitch guy with the instructions I found. He looked at them and said: "yep, that's how we do it." So we had a slight miscommunication over the phone. All is well in our pink house.

[2airishuman]

well it's just too bad that...

the geo' ibc is DISABLED as the sop for disc brake systems...

really this thread should be titles 'the general's integrated brake controller....

since henry's ibc, works just fine, thank you...

and my shopping for a new truck just became narrower....

cheers
2air'

[peegreen]

Originally Posted by thatismytruc

Picked up the new TV, and brought it straight to my hitch guy with the instructions I found. He looked at them and said: "yep, that's how we do it." So we had a slight miscommunication over the phone. All is well in our pink house.

I still question why he is hardwiring the controller and not using the Tekonsha harness available.

[biggoofball]

P:

Click on my first link (the how to). I shows what GM gives you now. I was able to salvage the short pigtail that the prodigy started with, but GM leaves 4 bare wires under the dash and two power wires (with ring terminals) near the relay/fuse box.

[peegreen]

Originally Posted by thatismytruc

P:

Click on my first link (the how to). I shows what GM gives you now. I was able to salvage the short pigtail that the prodigy started with, but GM leaves 4 bare wires under the dash and two power wires (with ring terminals) near the relay/fuse box.

There is no longer a trailer brake controller plug under the dash in the GMT900s Document ID# 1866253 2007 Chevrolet Silverado - 4WD -------------------------------------------------------------------------------- Subject: Information on Electric Trailer Brake Controller Wiring - Towing, Tow #06-08-45-008 - (10/10/2006) Models: 2007 Cadillac Escalade, Escalade ESV, Escalade EXT 2007 Chevrolet Avalanche, Silverado, Suburban, Tahoe 2007 GMC Sierra, Yukon, Yukon Denali, Yukon XL, Yukon Denali XL -------------------------------------------------------------------------------- Some customers may have questions on how to connect an electric trailer brake controller or where the brake controller pigtail harness is located. Starting with the new 2007 GMT900 full size utilities and pickups, there is no longer an electric trailer brake controller pigtail harness. The trailer brake controller wiring is now part of the Instrument panel wiring harness and the blunt cut wires are located under the left instrument panel, behind the data link connector. There are four blunt cut wires in this harness as described below.

Who woulda thunk it. What used to be plug n play is now a step back in time.