2016 Chevy 2500HD Duramax IBTC not locking trailer brakes

dmdomokos · 08-09-2016, 04:56 PM

I finally upgraded to a new 2016 Chevy 2500HD Duramax truck. Love it! But, I can't figure out if I have the integrated brake controller set correctly. The manual lever will NOT lock the brakes at 20-25mph as the manual says. But the manual also says if they don't lock, just set it to max (10) on the gain. I'm at 9.0, I can feel the trailer brakes working, but have never been able to "lock them". Is this how it works? Trailer is about 7,000lbs. Rockwood 2702WS Ultralite.

BandJCarm · 08-09-2016, 04:58 PM

Try this.

Hook up trailer. The auto setting has two tabs, left and right. "Pinch" them between your hand. Let off the brake (on level ground) and let the truck and trailer inch forward on its own.

When it starts going, pinch the two tabs together. When the trailer stops, that's the correct setting. It should display the setting on the DIC and be set.

Big Red and 30WR · 08-09-2016, 05:02 PM

Can`t say either way but my 16 Ram is the same way . Set the controller @ 10 and manually slide it and not trailer wheel lock up . just feel the brakes working .

Electra glide · 08-09-2016, 05:03 PM

Quote:

Originally Posted by BandJCarm

Try this.

Hook up trailer. The auto setting has two tabs, left and right. "Pinch" them between your hand. Let off the brake (on level ground) and let the truck and trailer inch forward on its own.

When it starts going, pinch the two tabs together. When the trailer stops, that's the correct setting. It should display the setting on the DIC and be set.

That's How I set my fifth wheel in my 2015 2500HD.

dmdomokos · 08-09-2016, 05:06 PM

Quote:

Originally Posted by BandJCarm

Try this.

Hook up trailer. The auto setting has two tabs, left and right. "Pinch" them between your hand. Let off the brake (on level ground) and let the truck and trailer inch forward on its own.

When it starts going, pinch the two tabs together. When the trailer stops, that's the correct setting. It should display the setting on the DIC and be set.

So I think you mean the manual slider. Pinch and one side slides to the other which is fixed in place. At max "Pinch" gain says 10.0. I am going to start from a stand still, let the truck and trailer idle forward, then pinch and when the truck and trailer stop via just the trailer brakes, that's the setting. Do I have that right?

Big Rig · 08-09-2016, 05:48 PM

Sounds like trailer brakes are out of adjustment. Mine lock up at 6 and I run at 5.

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Bryan V. · 08-09-2016, 05:53 PM

I have mine set at 5 but leave the exhaust brake on.

dmdomokos · 08-09-2016, 06:25 PM

Quote:

Originally Posted by Big Rig

Sounds like trailer brakes are out of adjustment. Mine lock up at 6 and I run at 5.

Sent from my iPad using Forest River Forums

Not sure they are, I had a Prodigy P3 in my previous TV and they locked at 4.5, smoke and all. I ran at 3.5 to 4.0. That's what's throwing me about the IBTC. It also doesn't seem to be proportional like the P3.

BandJCarm · 08-09-2016, 06:31 PM

Quote:

Originally Posted by dmdomokos

So I think you mean the manual slider. Pinch and one side slides to the other which is fixed in place. At max "Pinch" gain says 10.0. I am going to start from a stand still, let the truck and trailer idle forward, then pinch and when the truck and trailer stop via just the trailer brakes, that's the setting. Do I have that right?

Don't "max pinch". Just pinch together JUST until the trailer stops without your help from TV brake. That's the setting.........

WolfWhistle · 08-10-2016, 06:03 PM

could there be settings on the GM like there is on my Ram 2500? Light and heavy plus light and heavy EOH? Also, brakes need to brake in if the trailer is new. Mine took several hundred miles after I abandoned the factory controller and installed the P3 to work properly.... now set on Boost 2, I can lock up the binders.
WW

dmdomokos · 08-10-2016, 07:14 PM

Quote:

Originally Posted by WolfWhistle

could there be settings on the GM like there is on my Ram 2500? Light and heavy plus light and heavy EOH? Also, brakes need to brake in if the trailer is new. Mine took several hundred miles after I abandoned the factory controller and installed the P3 to work properly.... now set on Boost 2, I can lock up the binders.
WW

I have not found anything on the IBTC I can set for different trailer sizes like the P3. (I loved the P3). The trailer has about 5,000 miles on it and they did lock up with the P3. Not even sure if the dealer can adjust the IBTC. Anyone know?

davel1971 · 08-10-2016, 07:56 PM

I'm set at 5.5 with a 12,000 lb trailer and it stops fine and will lock if I stop hard enough. I'm betting trailer brakes are out of adjustment or grease seals have contaminated brakes.

asquared · 08-10-2016, 08:20 PM

Mine never locked up either. I am set at 6 with 12000 lb fiver and it works well.

NMWildcat · 08-10-2016, 08:28 PM

Several of my friends that have newer trucks (Chevy and Ford) all gave up on their IBTC and installed after market controllers and no longer have any braking problems.

WolfWhistle · 08-11-2016, 08:02 AM

I replaced the brake wiring from J box to all hubs with 10 AWG; up from what looked like 14 AWG (Forest River) and 16 AWG (Dexter - through the axles). It seemed to help a little, but not as much as the P3. I did the wiring first ... maybe with the P3 the lower voltage drop helps as well??
WW

Koz · 08-11-2016, 08:59 AM

I just had this happen to us the other day. I have a 2015 2500HD. Tuesday as we were leaving the campground hauling our trailer, the truck told me of a brake controller issue. I pulled over and found that the extra slack in the emergency brake engagement cord had looped over the hitch slide position lever and yanked out the brake cable on a right hand turn. I put the brake pin back in which released the the trailer brake. The truck however was not a "happy camper". It continued to tell me that there was a brake controller problem. Even with repeated shut downs of the truck and checking of all connections, the truck would not recognize a good controller condition. Then as I.... "meditated with expletives".... I turned on the truck to keep the air conditioner going for the wife and dogs, and low and behold it now was working fine. One last engine power cycle and connection check convinced me it was safe to proceed. I agree with the one poster above that indicated that the Truck's engine controller does not like to see a voltage feeding back from the trailer when that disconnect pin is pulled. They must have a current detection scheme whereby it protects itself but opening up the circuit for some duration after that fault condition. If you are having a chronic issue with that trailer I would definitely check that disconnect is not shorted in some manner.

thebrakeman · 08-15-2016, 03:59 PM

The goal of ANY proportional trailer brake system (integrated or aftermarket) is to have the trailer brakes almost lock up during a panic service brake apply. During a panic service brake apply, a proportional controller will send back whatever voltage you have set as it's maximum (full manual apply).

This MUST be determined after the brakes are warmed up a bit (I do light applies in the neighborhood until I can smell them a bit with the windows down). And the manual applies MUST be done dynamically (they recommend from 25mph), and NOT with the little static "pinch method" as some suggested earlier. No offense, but that is a dangerous recommendation that will have you setting the brakes far to light.

The OP said that his P3 was working flawlessly, and could lock up the brakes. So there is no need to suggest that his brakes need adjusting, or there is grease on the pads. The trailer is fine. The problem is the truck. If you warm up the brakes, and follow the procedure, and can't lock the brakes, then take the truck to the dealer and say fix it. If they can't or won't have them disable the system at their cost, and reinstall the P3.

Plain and simple folks:
If you can't set trailer brakes right up to the point of pending lockup, then you will not have the shortest possible stopping distance in an emergency.

dmdomokos · 08-15-2016, 06:27 PM

Quote:

Originally Posted by thebrakeman

The goal of ANY proportional trailer brake system (integrated or aftermarket) is to have the trailer brakes almost lock up during a panic service brake apply. During a panic service brake apply, a proportional controller will send back whatever voltage you have set as it's maximum (full manual apply).

This MUST be determined after the brakes are warmed up a bit (I do light applies in the neighborhood until I can smell them a bit with the windows down). And the manual applies MUST be done dynamically (they recommend from 25mph), and NOT with the little static "pinch method" as some suggested earlier. No offense, but that is a dangerous recommendation that will have you setting the brakes far to light.

The OP said that his P3 was working flawlessly, and could lock up the brakes. So there is no need to suggest that his brakes need adjusting, or there is grease on the pads. The trailer is fine. The problem is the truck. If you warm up the brakes, and follow the procedure, and can't lock the brakes, then take the truck to the dealer and say fix it. If they can't or won't have them disable the system at their cost, and reinstall the P3.

Plain and simple folks:
If you can't set trailer brakes right up to the point of pending lockup, then you will not have the shortest possible stopping distance in an emergency.

Good info. I do have a clarification though. If I have the OEM controller set at say 5.0 and apply the manual slide, will the max end of the slide only be 5.0? Should I set the gain to 10.0, then do the 25 mph test and see if/where it locks up at , if at all?

aufinger · 08-15-2016, 06:53 PM

Quote:

Originally Posted by NMWildcat

Several of my friends that have newer trucks (Chevy and Ford) all gave up on their IBTC and installed after market controllers and no longer have any braking problems.

The IBC was totally lame in my 2016 Tundra. When set on 5 at 20 mph the slider locked up the TT's brakes but when actually driving I couldn't feel the trailer brakes even when it was set on 10. Dealer tested it and said they're working as designed. I replaced it with a Tekonsha P3 and I'm happy as can be. Larry G.

RangeMaggotBob · 08-18-2016, 11:53 PM

I run mine on "8" heavy electric even though my RV is less than ten thousand pounds. I assume it's correct because when I go to stop, I just barely have to touch my brakes. I don't really feel the trailer brakes, but like I said, it stops real easy so I guess it's okay.

I've never been able to lock them up, but I don't remember seeing anything about that procedure in my manual. To the brake meisters: am I alright like this?!?

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