Trailer Brake/Controller Issue

[HATHAWAY]

I have friend. My friend is towing a XLR Thunderbolt, tri axle, with 2019 Ford 350 DUALLY. this is his first trip rowing the new setup. His problem. while towing at highway speeds, often but randomly the trailer brakes will engage. Not so as to slow down the vehicle. It seems to cycle about every second.
when he applies the vehicle brakes it will usually stop for awhile. The brakes do work and his vehicle does not show a "trailer connection" error. Has anyone had a similar experience? Also, the truck WIFI shuts down after 10 minutes. He has to restart it, byt shutting off the vehicle. Thanks, Ron

[DieselDrax]

Being a 2019, I’d take it to the dealer and have it checked out. That’s what the warranty is for. Especially if he’s also having Wi-Fi issues. There could be some electrical or module issue that is interfering with both the Wi-Fi and brake controller.

[The Goon Squad]

Clarification on Ron’s brake question. (I am the friend)

2017 XLR Thunderbolt 415AMP. Triple axle. Fewer than 1500 miles. New to me this spring.
2019 F-350 DRW

When applying pressure to brake pedal the trailer brakes pulse every second. I can see a corresponding report on the gain meter on dash flashing to full gain and off with each pulse. If I release pedal and reapply the brakes will usually engage as expected with smooth, even pressure. If I release pedal again and reapply sometimes it goes back to pulse and other times it remains smooth.

It is not antilock brakes on truck. Trailer has fewer than 1500 miles logged but is new to me this spring.

[DieselDrax]

Still suggest visiting the Ford dealer. They may have a software update for the brake controller to address this. The trailer brakes won’t affect what the brake controller outputs, that is 100% an issue with the brake controller. So if you’re seeing the gain cycling from 0 to 100% and back then that’s a Ford issue.

[The Goon Squad]

The local dealer is booked out until after we return to MN.

I have read in other forums that people had similar issues and found the wires running from one side of the RV to the other to have worn through the insulation. I would be surprised if this is the problem due to low usage of the RV to date.

Is there an actual brake controller onboard the coach or is it just wires from 7 pin to axles via breakaway switch and battery?

I also read about the breakaway switch having issues. I checked that and everything looks good.

Connections in junction box appear tight as well.

I guess I start tracing wires and looking for any worn insulation.

[babock]

Out of curiosity, does the trailer have electric over hydraulic brakes?

[The Goon Squad]

Electric only.

[rsdata]

I recently had a truck warranty issue. Had to call 3 dealers to get an appointment within the week, as the other two were offering me 3-4 weeks out appointments. Surely there are other Ford dealers not that far away.

[The Goon Squad]

After spending many hours inspecting trailer wiring, truck wiring, adding another ground wire, looking through forum threads and more, I figured out the issue.

The 2019 Ford brake controller has two settings available. The first is the standard Gain setting and the second adjusts the Response Time of the brakes. I had tested the brakes with high and low gain with the same result of pulsing brakes. As I had found no other cause for the problem I decided to reset the trailer settings in the truck computer.

As I rebuilt the settings I arrived at the Response Time setting. Being that the TT is a heavy rig I had originally figured that the more aggressive response time was what I wanted in order to have the most control of the trailer. I had forgotten about the second setting in the controller and tried the medium setting in the new setup for the trailer. This less aggressive setting fixed the pulsing problem completely and now the truck/trailer combo functions as it should.

The Ford service guy at the dealer either did not know about the extra settings or was not aware of the effect of it on some trailers as he did not bring up the option as a fix.

Thanks for all the suggestions as I worked through the problem.

Ben

[DieselDrax]

Glad you got it sorted out and it was only a setting that needed to be changed!