Possible trailer braking issue on a 2021 TRD Pro

So I hooked up my Coleman pop up yesterday to my TRD Pro and on the way home the trailer brakes are not applying. Gives me a yellow triangle annoying beep every 20 sec. dash said wiring, something else sorry I didn’t take pic and read owners manual. So I pull over and set it up with electric brakes thinking that was it since it’s my first time towing with this truck. Take off and same thing. All the lights work fine but no braking action no matter how high I set it for. I’m not 100% sure it’s not a trailer issue yet till I pull the wheels because trailer has sat for 2 years. Went online and found MANY complaints about the stock controller not working correctly and dealer reflashing ECU. Most were pre 2018. Anyone know if this is still a problem ? A lot of people just went with a prodigy P3 controller which I think is crazy after spending 52 k on a truck. Thanks.

 

Any one ????

 

First thing I’d do is disconnect the trailer cord from the truck, pull the breakaway and tug test the trailer brakes.

Then use a good old bulb-type test light to test for power on the bottom right pin (blue in diagram below) of the truck connector while a helper activates the manual slide on the brake controller.

 

That’s what I was planning when I get home. No tools at the weekend place. Thanks. I was curious if any newer tundras still had the issue.

 

So blue supplying trailer brake is dead with foot brake and trolly. Dealer appointment This Thursday. Trucks not even 3 months old

 

Keep us posted. I haven’t seen many / any complaints with the brake controller on later model trucks myself, unlike on 17-18’s. Hope they get you fixed up in short order.

 

Will do.

 

So dealer said There was a TSB for this issue but when he hooked up the computer they are only for pre 2018. I did have a code for negative voltage at the trailer wire. Tech was very cool since I’m also a mechanic he let me hang with him while he went through it. Told me he was calling Toyota because blue wire was dead and no visible sign of any thing. Also zero issues nationwide with my issue on any other tundra so far. Came back and Said it’s not supposed to have voltage unless it senses a load. I asked him to confirm with another tundra and he agreed and came back and said it was the same. Came home and pulled wheels because my linings were worn and replaced the whole backing plate assemblies because you can just find linings and also replaced the berg plug and the butt connectors I found in the harness leading back. Plugged it in and it acknowledged the trailer and brakes work fine plus no more beeping on the dash. Not sure which one fixed it but I believe it was in the trailer unless he did something with software when I wasn’t there which I don’t feel he did. I can see what the forums say about not enough braking power though. I have the gain at 10 and it “slows” you down but def not a lot of braking. Trailer is only 3000lbs so it should be alright. Hope this helps others.