GM integrated brake control

[Bob_Vaughn]

I was at the rv repair shop this morning for the second time about my brake controller not working....It was determined that the integrated control was not functioning and was sending a constant 3.6 volts to the brakes. As I was leaving there was another guy there with a truck like mine that he only had 2 weeks and his brake control did not work either. Is this an inherent problem with GM integrated controllers?

[minnow]

If you have a IBC, can you disable it and install a conventional controller ? If that is the case, it would seem that if the trailer brakes work well with the aftermarket controller, then it would indicate a problem with the IBC. If the aftermarket controller also had inadequate braking then it would lean towards bad connections/wiring ????

[Lynnmor]

justafordguy wrote:

CarnationSailor wrote:

APT wrote:
Carnation, can you adjusted the trailer brakes?

The brakes are self-adjusting so I shouldn't have to adjust them. However, I could look into that next Spring.

I'm not unhappy with the current braking. It's just I'm not sure I'm getting the braking power that I should.

I thought the same thing about my new Gateway. It has self adjusting brakes and even with the controller set to 10 the brakes are marginal. I checked the adjustment last weekend and they were way to loose. I'll be towing it in a few weeks and hopefully it will be better.

The brake manufacturers have a runout tolerance that is too great for self adjusters to work properly. You might get lucky and have good drums or maybe not. Adjusting manually is still the best.

[BarneyS]

Bob Vaughn wrote:
How would you know if your brakes were self adjusting???

The brake drum will have a cable that runs to the shoes. See this post by member Jbarca for pictures of what they look like.
Barney

[Bob_Vaughn]

How would you know if your brakes were self adjusting???

[justafordguy]

CarnationSailor wrote:

APT wrote:
Carnation, can you adjusted the trailer brakes?

The brakes are self-adjusting so I shouldn't have to adjust them. However, I could look into that next Spring.

I'm not unhappy with the current braking. It's just I'm not sure I'm getting the braking power that I should.

I thought the same thing about my new Gateway. It has self adjusting brakes and even with the controller set to 10 the brakes are marginal. I checked the adjustment last weekend and they were way to loose. I'll be towing it in a few weeks and hopefully it will be better.

[trail-explorer]

mkirsch wrote:
... Trailer manufacturers are notoriously cheap, and use substandard wire for the brake connections. They tend to use 12ga or 14ga wire when it should be 10ga or possibly even 8ga.

Voltage drop in 12VDC systems is bad.

ANd they often times use crappy methods of crimping the axle wires to the trailer wires. I've even seen WIRE NUTS used!!!

[Bob_Vaughn]

bailer6334 wrote:
Bob,

I was on another forum and they were discussing the same problem you have. Sorry can not remember the forum, but the cause was a bad connection between the truck wiring and at least one of the pins in the 7 pin plug. Not enough voltage ( I think 12-15 volts is normal)was going through the pin to activate the brake controller properly. GM techs did not find the problem, a trailer hitch tech discovered it.

Hope this helps isolate the problem.

I have a 7 way plug tester and the brake light just flickers when I apply the trailer brakes, a trip to an rv place cost me 295 bucks and was told everything was rewired from the ITC back to the plug. Still did not work. A trip back with two techs working on it telling me the controller was not sending voltage back to the trailer pin. Got a 50% discount and paid 115 bucks. Took it to the dealership to have the ITC replaced. They called and said nothing was wrong and they hooked it to a TT and the brakes worked......BUT they did not tow it just listened to hear the magnets. I took it hooked it to my 5th wheel and with my wifes help I could just barely hear the magnets and there was very little resistance when doing a pull test. I am at a wits end as to what my problem is.....It is keeping me awake at night.

[mkirsch]

CarnationSailor wrote:

APT wrote:
Carnation, can you adjusted the trailer brakes?

The brakes are self-adjusting so I shouldn't have to adjust them. However, I could look into that next Spring.

I'm not unhappy with the current braking. It's just I'm not sure I'm getting the braking power that I should.

You probably aren't. Trailer manufacturers are notoriously cheap, and use substandard wire for the brake connections. They tend to use 12ga or 14ga wire when it should be 10ga or possibly even 8ga.

Voltage drop in 12VDC systems is bad.

[bailer6334]

Bob,

I was on another forum and they were discussing the same problem you have. Sorry can not remember the forum, but the cause was a bad connection between the truck wiring and at least one of the pins in the 7 pin plug. Not enough voltage ( I think 12-15 volts is normal)was going through the pin to activate the brake controller properly. GM techs did not find the problem, a trailer hitch tech discovered it.

Hope this helps isolate the problem.

[jareddustin]

no issues on my 2009 but if go over to the duramax fourms you can read more in detail about other people having issues and what they needed to do, tons of info over there

[Elbert]

2014 2500 HD with no issues with the IBC. I did have some problems with the trailer connection and wiring which I solved on the trailer side. Just got back from a 3200+ mile trip.

[Bob_Vaughn]

My 2013 GMC has never stopped my 5th wheel like my 2000 Chevy did with an aftermarket control. Mine has never been right from day one, I just thought it was the nature of the beast.....NO VOLTAGE goes to the brake connection on my plug.....

[allen8106]

I have a 2013 GMC. My controller seems to work not great but ok. I`m thinking maybe it could be a bad connection or possibly undersized wire on the camper.

[Michelle_S]

OK, here's the story on GMs. The installed Brake controller send a digital signal down the line (approx 3 to 4 volts) looking for the correct resistance. Once it see the correct resistance it will give the "Trailer Connected" message and will now supply the proper voltage and current to the brakes. What happens these "So called Techs" put a voltmeter on the brake control line and read that digital signal and tell you there is a problem with the controller which is untrue. I have over 86K on my 3500 and 90 to 95% of that mileage is towing heavy without any trailer brake problems.