Curt TriFlex brake controller problem

[TopoTony]

I’ve been having an issue whereby the display on the controller will intermittently flash a high number as if it’s activating the trailer brakes at close to maximum strength. But I am not touching the brake pedal at all, and, I do not feel any braking happening when this occurs. This happens even when I'm simply sitting at idle without the brakes depressed. It is a bit concerning tho, when I'm driving down the highway and see the curt display flash a big number. It’s acting as if I’m depressing the brake pedal extremely hard.

I’ve even swapped the controller with a new one of the same model and the problem is still there. Could it be an issue with this model controller? I really am stumped on how to troubleshoot this problem. I thought it might be some sort of short in my truck's wiring, but that's unlikely. It's a very low mileage Tundra. I easily found the connector plug under the driver's side dash and fit it perfectly into the curt with the supplied cable.

Maybe I need to buy a different model controller and test it.

Appreciate any advise..thanks

 

[Gary RV_Wizard]

Does it ever do that without the trailer connected? If not, I'd be skeptical of a truck short. But what about a trailer wiring short? If the trailer brake wire momentarily shorts to ground, it could look like a load on the controller but no amps flow to the brakes themselves (so no braking felt). And another controller would show the same symptom.

 

[TopoTony]

Hi Gary. Yes, it does it without the trailer connected. That’s why I thought it might be some inherent weird compatibility issue with my truck and that particular controller.

 

[Kirk]

The same thing as Gary suggested could also happen if there is a similar problem but in wire harness or the pug on the truck side of things. The issue could be anywhere from the controler to the rear bumper/plug.

 

[TopoTony]

So…maybe a short anywhere from the controller to the plug? How would one test for something like that? I’ve got my trusty volt meter.

 

[8Muddypaws]

Check the center connector on the trailer connector first. I had similar problems and that was the cause. It was loose.

 

[Gary RV_Wizard]

Hi Gary. Yes, it does it without the trailer connected. That’s why I thought it might be some inherent weird compatibility issue with my truck and that particular controller.

Then I would suspect the wiring from controller to plug, including the plug itself. Start problem isolation at the plug end, which I deem to be the most likely place.

 

[TopoTony]

Check the center connector on the trailer connector first. I had similar problems and that was the cause. It was loose.

That’s a good clue. A couple years ago a friend took the truck connector apart, where the trailer plugs in, to troubleshoot a different issue that turned out to be the actual brakes on the trailer. (that’s another interesting story) Possibly something became loose in that plug in connector.

 

[Kirk]

How would one test for something like that? I’ve got my trusty volt meter.

With the problem being intermittent, that makes finding the cause much more difficult. Like Gary, I would look at the plug first and a loose connection is very possible because it comes and goes.

 

[CharlesinGA]

The center, round pin on the trailers 7 way is reserved for the backup lights.

Charles

 

[CharlesinGA]

Do the trailers brakes work? What is the year, make, model of truck.

 

[TopoTony]

Do the trailers brakes work? What is the year, make, model of truck.

2014 Tundra. 39k original miles. Got it from the 1st owner that kept it garaged, @ 29k miles. I’ve put 10 on it hauling our little hideout. Yes, the trailer brakes work fine. And when I see the controller flash like I’m pressing the break, nothing is braking at that point. It’s as if some errant signal is telling the controller that braking is happening, but it isn’t.
The hitch plug, and the harness lead under the dash are all factory installed. It would be unusual for any of that to be malfunctioning, considering the young age of the truck and that every other aspect of this truck is working perfectly.
I’m going to run some tests by basically plugging it all back in and seeing what happens. I haven’t been out towing with it in a year, so maybe it fixed itself, ha ha.

 

[gwinger]

If you are going to the trouble to unplug everything use some good contact cleaner with lube on all the plugs, including the 7 pin connectors.
My 2015 Silverado gives me trailer brake errors every so often, with or without the trailer connected. I give the 7 pin connector a shot of DeOxit D5 to remove any corrosion and/or water in the plug.

 

[TopoTony]

Possible problem identified! I picked up a Tekonsha P3 to test the issue with the Curt, and while reading thru the installation instructions I came across some small print that said to keep the unit away from cell phones. Bingo! It immediately rang a bell, since I frequently see the effects of having my iPhone too near to various other electronic devices. Typically, the speakers in my audio studio will broadcast errant pulsing static noise if my phone is within a foot or so. I also see the controller for some battery powered led's flash it's mode led's if my phone is sitting next to it.

I have not swapped the Curt back into position and probably won't. The Tekonsha has not displayed the problem. I think it is less susceptible to the phone interference. I'm fairly confident this was the cause for the original issue with the Curt. It's response to the signals emanating from the iPhone was to show errant activating numbers in the display. Only wish I had seen some warning about the proximity of phones to it, before I spent $130 for a new unit and harness. BTW, Curt sent me a new harness for free, to test the problem, but it did not help.

 

[John From Detroit]

There is a podcast. One episode I watched live they kept getting a noise in the audio feed, I knew it instantly. Cell phone "Handshaking" with tower.

 

[TopoTony]

There is a podcast. One episode I watched live they kept getting a noise in the audio feed, I knew it instantly. Cell phone "Handshaking" with tower.

I'm surprised I didn't think of that sooner, but at least the answer eventually appeared. I would not have thought a brake controller would be susceptible to that type of interference.