GM Integrated Brake Controller

[Smax]

Hi All -

I reviewed some of the prior posts concerning issues with the GM controller. Save me a little research and tell me what you think.

Truck is new (2016 2500 HD). Trailer is 2000 Sunnybrook.

I am getting the trailer connected/check trailer wiring/check brake wiring...

Never had issues with connection beyond the occasional cleaning etc. Got the new truck and have had nothing but problems. Figured it was the old pigtail so I put a new one on. Same issue, but I did notice it does not seem to plug in firmly. Shook the pigtail and noticed I was getting the warnings. So I wrapped it with a velcro strap. Went on a short trip last week. Still got warnings, but mostly only when I hit a bump, and then it would continue to ding, ding, ding, ding. I'm still hearing dings...

I had to pull over once and redo the velcro. It stopped for quite a while..until I hit a bump.

Checked the trailer wires best I could and did not seem to matter if I shook any of the obvious wires under the trailer. So I think it is right at the connector...

Connector on the truck is the problem?

Max

[Smax]

That is the main feed wire from the pigtail to the magnets on the driver side. The axle wire is consistent with the size of the magnet wires. As I recall you can go big to small, but not small to big. I suppose you could make the 10 gauge a main feeder wire all the way, but that's not how it is from the factory. The magnet wires are only 18 ga. You would think it would be best to have the larger wire feeding each brake, but they seem to work fine as is.

I read another suggestion to install a terminal block and make the 10 gauge a home run wire to each brake. That way one failure won't knock out the whole system. Seems like a good idea. My guess is the brake controller would not identify a failure this way.

[Lynnmor]

Smax wrote:


For those wanting to replace the wires in the axle this is what I did:

Go to Lowes/HD and get a 20' spool of 16 or 18 gauge double stranded lamp cord wire (just like what you see on the lights you plug in). Each axle used 8' of wire. Get a bag of 12" tie wraps. I used about 10 per axle.

eTrailer recommends 10gauge wire as does many others that want to reduce voltage drop. It might not be easy to fish thru an axle, so simply wire tie it to the back side.

10 gauge

[Smax]

Hopefully that's all it is. As crazy as it may sound mine was fine after replacing the plug too. It started acting up again after I had it inspected. The wire inside the axle was frayed about 6" long on one side with many broken strands.

[mooky_stinks]

I was getting the "trailer disconnected" warning several times per trip. I just installed a Pollack plug on the trailer and on my first trip out, no warning so far!

[Smax]

Thanks, and I agree about the controller. I just wish they had a way to silence the "ding ding, ding ding". I may have to seek counseling to stop the dings in my head! The brake circuit fuse blew at one point on the trip. Dings stopped, so did the brakes. I replaced it and it never blew again...

Chasing down low voltage electrical problems is almost impossible when it is intermittent. I called a well known RV dealer on the road to make an appointment to have them find it. The service person "advised" me that they Charge $140.00 an hour labor and there was no guarantee they would find the culprit. Needless to say I would rather put some pennies in a slot machine...My guess is they would have checked those wires going through the axles first. They seem to be the weakest link. Hopefully Dexter is doing something better now?

Knowing what I know now - removing and replacing the axle wires would be the first thing I would do. It is cheap, simple, and in my judgement necessary regardless of failure.

On a positive note, I was very impressed with my new 2016 Duramax with the exhaust brake. We downsized the RV years ago and the Sunnybrook is less than half of what the truck can handle. The exhaust brake performed as advertised, but you still need brakes when you need them!

For those wanting to replace the wires in the axle this is what I did:

Go to Lowes/HD and get a 20' spool of 16 or 18 gauge double stranded lamp cord wire (just like what you see on the lights you plug in). Each axle used 8' of wire. Get a bag of 12" tie wraps. I used about 10 per axle.

Go to the plumbing section and get 3/8" clear tubing. I think it came in a 20' roll.

Go to an auto parts store and get a box or two of 16/18 gauge weatherproof (shrinkable) crimp connectors. You should only need 4, but I messed a couple up...

Disconnect your battery. There "shouldn't" be any juice going to the brakes unless activated, but you may have a different problem.

Measure your axle for the length of the clear tubing. I used the existing exit holes of the wires to be replaced. In my case it was 6'. Cut the tubing to length. Fish the cord wire through the tube, leaving a foot or so on each end. I had a wire fish for this.

Crawl under the trailer and cut the wires from the axles where it connects to the magnet wires. Remove the old axle wire. Strip the ends of the magnet wires while you are down there and crimp on the new connector. Install the tubing along the top side of the axle with tie wraps.

Cut the new wire to the appropriate length, strip and crimp to new connector. Lightly tug to make sure it is secure. Use a heat gun to shrink and seal the new connector. Wrap with electrical tape for extra precaution. Tie wrap the new connection to keep it stable while moving.

Just a shade tree mechanic, so easy on the critiques!

Hope this helps.

Max

[ktmrfs]

Smax wrote:
So here's a follow up almost a year later. I changed the pigtail to a pollack. Still had the problem. It would come and go so I checked all the connections on the backside of the brake plates. A couple were not secured like hey should be so I tie wrapped them. The problem was 98 % gone. Hmmm, so I have a bad connection in one of those bundles - front axle. I got real ambitious and ordered new self adjusting brake kits and drums. I found the problem. It was the wire INSIDE the axle that connects the left brake to the right. It was totally frayed. Securing the wires at the drums just stabilized it. I am really glad I did this. The brakes were in real bad shape. They had cracks running down the middle of each pad, and being 17 years old the hardware was due. New drums too. I found this YouTube after I was done .... Hope this helps someone having similar issues.
https://youtu.be/21QFaEw3NCE

so the factory brake controller did indeed do it's job and was detecting an intermittent connection and warning you about it. And rather than ignore it, you did the correct action and chased it down till you found it. Good job. And an aftermarket controller would likely have never indicated a problem.

Chock up another plus for the integrated controllers.

[GWolfe]

Thanks for the update, so many times we never hear about the resolution.

[Smax]

So here's a follow up almost a year later. I changed the pigtail to a pollack. Still had the problem. It would come and go so I checked all the connections on the backside of the brake plates. A couple were not secured like hey should be so I tie wrapped them. The problem was 98 % gone. Hmmm, so I have a bad connection in one of those bundles - front axle. I got real ambitious and ordered new self adjusting brake kits and drums. I found the problem. It was the wire INSIDE the axle that connects the left brake to the right. It was totally frayed. Securing the wires at the drums just stabilized it. I am really glad I did this. The brakes were in real bad shape. They had cracks running down the middle of each pad, and being 17 years old the hardware was due. New drums too. I found this YouTube after I was done .... Hope this helps someone having similar issues.
https://youtu.be/21QFaEw3NCE

[deltabravo]

SouthpawHD wrote:
As others have said, it's a known problem that the GM male plug doesn't always make a solid connection.

It's not the GM receptacle that has the fault, it's that many trailer cord manufacturers aren't building to the SAE diameter spec for the plug.
I've had several RV dealers as well as several GM truck dealers tell me this.

[deltabravo]

Smax wrote:
Figured it was the old pigtail so I put a new one on. Same issue, but I did notice it does not seem to plug in firmly. Shook the pigtail and noticed I was getting the warnings. So I wrapped it with a velcro strap.
Max

The problem is most likely the undersized connector on the trilaer plug, which doesn't fit tightly in the truck receptacle

Smax wrote:

Connector on the truck is the problem?

Max

Highly unlikely. The problem is most likely the undersized connector on the trailaer plug, which doesn't fit tightly in the truck receptacle

[ktmrfs]

trail-explorer wrote:
I can't seem to find the bulletin I thought I'd seen, but what I have found is multiple recommendations to use a "Pollak" brand connector / pigtail on the trailer, as they are a better fit than Bargman or Hopkins.

absolutely. I found the pollak to be way better than bargman that was on my two trailers.

[SouthpawHD]

Take a small screwdriver and on the female ends, use the screwdriver to push the female ends tighter together to make a better connection.

As others have said, it's a known problem that the GM male plug doesn't always make a solid connection.

[JIMNLIN]

I pull GN and bumper pull flatbed trailers with the wifes '16 1500 4x4 chevy with GM controller. Works much better than the Prodigy in the 2500 Dodge....pulling the same trailers.

Some times ground wire(s) can be a pain.

[msjdbman]

I use nothing but Pollack connectors and never have an issue. The Hopkins brand look pretty cheaply made to me.