Trailer brakes stopped working

[Disneyfan]

Hi all,

We are not getting any output from the GMC trailer brake controller to our Escape 5.0 TA trailer. All the other connections work ie. lights, charging. We are on the road and at next stop we will be checking and troubleshooting again. Any ideas?

Thanks so much,
Mary and Rick

[Bayner]

There's a lot of individual fuses for the trailer tow package in the truck. One will be for the brake output. I would start with checking that. Sorry, I can't say where or which fuse number. Maybe someone else can fill in the blanks.

[ColoradoSwany]

I had that issue on our last outing. Fuses were fine, but our prior outing involved a lot of dusty gravel roads. Solved issue by spraying an electrical contact cleaner solvent on seven pin connectors. I always carry that stuff in our Escape and it has been useful.

[Ooshkaboo]

Just had my wheels pulled off for check on the factory lube, brakes.

Everything was lubed up fine, but one of the wheels brakes on each side wasn’t working.

Turns out the problem with wire connectors many on here have had hasn’t been addressed.

[splitting_lanes]

So, we fixed it, Disney Fan is traveling with me and posted the problem. Here’s what I did

I pulled the emergency disconnect on the trailer, and yep, couldn’t move. Brakes work.

Found the fuse in the fuse box, it was fine.

Broke out the volt meter. 0 volts on the pin with the brake activated.

I had Trademasters install an additional 7 pin connector in the bed… which I discovered didn’t charge the trailer as well as using the bumper mounted factory plug. So, I removed it from the circuit, hooked it all back up, and boom! We have brakes again.

Thanks all!

And thanks to those on the road that helped!

[Disneyfan]

Hi,
Thank you all for the helpful suggestions. We are safely on the road again with working trailer brake connection. After checking the truck fuses (all ok), and no voltage measuring on GMC pins; splitting lanes, my hubby, disconnected the installed 7-pin from trailer hitch installation and that finally did the trick. So now the GMC Canyon 7-pin connection that failed before is working perfectly. Yay! My hubby said now he will be able to tailgate again. No emoticon here but it would be an eye-rolling emoji for sure!
Appreciate such a quick response from all. Totally impressed with this community. Looking forward to enjoying some you in-person at the Mississippi River Rendezvous next week.
Best,
Mary (Disneyfan)

[TahoeJoe]

Glad you guys got it fixed! So you think it was just a defective/failed part installed by Trademasters, or was it a labor issue, i.e. improperly installed? I'm curious for my own purposes, in case mine that was installed ever has this issue...

[JohnK]

Originally Posted by Ooshkaboo

Just had my wheels pulled off for check on the factory lube, brakes.

Everything was lubed up fine, but one of the wheels brakes on each side wasn’t working.

Turns out the problem with wire connectors many on here have had hasn’t been addressed.

I’ve had to rewire and modify my brake wiring for the same reason. Like the exploding cooktop, brake failure must not be serious enough to be addressed by the manufacturer till something bad happens. The entire industry, stick built and fiberglass needs potty training.

John

[Disneyfan]

Hi TahoeJoe,
Splitting_lanes says it's too early to tell. He says, "Gonna try some contact cleaner on the pins" as suggested previously. We still found a connection issue today but per splitting_lanes "it's mostly working." Going through rolling plains of Nebraska headed for Sydney. Beautiful day!
Disneyfan

[kym]

I have had the same problem with both my previous 17B and the current 5.0TA towing with a GM Silverado. A friend who also tows with a GM Canyon, who is a HD mechanic, had the same issue with his 17B. While towing we both experienced a dash message 'check trailer brake connection' or check trailer connection. GM 7 pin connectors are designed with the lock tab on the truck side on the bottom allowing the weight of the trailer plug-in to pull down on the connection particularly on rough roads or over bumps. On his recommendation we changed the truck bumper 7 pin connector to a 7 pin connector from an auto supplier with the lock tab on he top of the connection. Result is no more messages. One other thing that we had both experienced was a surging in brake force at times. Seems the intermittent connection problem was also affecting brake efficiency when least wanted, if ever. Our experience is that this issue is a GM thing easily fixed.

[brroberts]

My ‘21 Ford Ranger has the same bottom tab 7 pin. I wish it wasn’t that way, but it hasn’t messed with the brakes - yet. I’ll have to keep an eye on this.

[BrooksWade]

I also experienced this problem on a Silverado. I changed the truck and trailer connectors to the EZ Connect system that uses powerful magnets to ensure a positive connection. I got it from E Trailer. I haven't had a problem since. Highly recommend.

[SkipperClyde]

My problem was a faulty trailer cord. The female connection had corroded and wasn’t making contact. Jammed some aluminum foil in the plug to get me home. Replaced the cord, all is well again.

[splitting_lanes]

Originally Posted by kym

I have had the same problem with both my previous 17B and the current 5.0TA towing with a GM Silverado. A friend who also tows with a GM Canyon, who is a HD mechanic, had the same issue with his 17B. While towing we both experienced a dash message 'check trailer brake connection' or check trailer connection. GM 7 pin connectors are designed with the lock tab on the truck side on the bottom allowing the weight of the trailer plug-in to pull down on the connection particularly on rough roads or over bumps. On his recommendation we changed the truck bumper 7 pin connector to a 7 pin connector from an auto supplier with the lock tab on he top of the connection. Result is no more messages. One other thing that we had both experienced was a surging in brake force at times. Seems the intermittent connection problem was also affecting brake efficiency when least wanted, if ever. Our experience is that this issue is a GM thing easily fixed.

That’s exactly what we are experiencing now that we removed the add-on 7 pin connector from the circuit and are using the GM lock tab down connector. I’ll look for a replacement for it that has the lock tab up.

[splitting_lanes]

Update on this issue.

The only connector I was able to find was OEM style with the lock tab down, so I replaced it with a new one and cleaned up the connector with a wire brush and contact cleaner. After I got all the lights working again ( one of the pins receivers wasn’t making contact) I thought the issue was resolved. We traveled a mile down the road, hit a bump, and got a message on the DIC to check trailer wiring.

I messed with different configurations of wiring and settings of the dc-dc converter for a thousand miles before I got it working solidly.

The solution to getting the 7 pin connector working with the lights and brakes was to switch back to the Trademasters installed 7 pin connector in the bed and disable the dc-dc converter. After I made this switch, we drove well over a thousand miles without a single issue.

I am convinced from all my efforts and readings that the GM upside down 7 pin connector is incompatible with anything high current, as it leaves the ground connector on the top of the 7 pin and it is the first thing to get pulled out when going over a bump. This results in sparks and cruft on the contacts causing it to fail.

People on GM forums alluded to GM suggesting that an independent ground be installed to maintain functional trailer brakes. “You can never have too many grounds”

Has anyone here installed an independent connector (I thought I had read that someone did) to run a hot and ground to the dc-dc converter?

What connectors did you use?