"TBC Not Available" and "Trailer Disconnected"

Picked up our new-to-us camper at the RV dealer, successfully added the trailer, but get a TBC Not Available message when I try to set the trailer brakes. Also, there is no output showing at all on the horizontal bar graph. When I moved the manual lever to see if I could get any Gain, I got a Trailer Disconnected message. I did see Trailer Detected and the RCTA shut off, but I had to manually turn off the Parking Assist function. The 7-pin connector is working - all the trailer lights work, etc. I am reading others have seen this. What did you have to do to get it fixed so the TBC system will work?

 

Is the trailer side wiring on the 7-pin correct? Sounds like it’s not getting the right signal to the TBC. That said, truck could have bad wiring too… but I would check the trailer first.

FYI Trailer is detected by the blind spot monitor sensors in the door mirrors.

 

quick correction, the blind spot monitor sensor is located in the rear bumper, the alerting is in the mirrors.

for OP @ThatQualityGuy, its entirely possible your trailer isn't wired correctly for brake controllers. Have you tested it with another vehicle or with an external brake controller? I had that same issue on one of our BSA troop trailers. our newest one was wired incorrectly from the dealer and I had to swap the pinouts.

 

Thanks for your input. My situation facts are these: 1) 7-pin plug is connected, 2) Trailer is being detected, 3) RCTA function is being disabled automatically, 4) Parking Assist is NOT being disabled automatically, and have to disable on the MID. Does all this mean the trailer is being detected by the BSM sensor (at the mirror) and not by the 7-pin connector (because the 7-pin connector on the truck is faulty)?

 

My next move it to try another trailer. Trying to find one locally to connect to. And I see the correction on the BSM alert from the mirrors. Thanks.

 

Following as I have the same issue, brake controller is not working on either travel trailer or 12' utility trailer. Checking fuse today, as brake controller had been working just fine previously.

2022 Tundra 1794

 

Did you ever get the brake controller to work?

 

Having the same issue. Did you find the fuse that controls this?

i was towing my camper and one of the wires that controls the trailer brakes on the camper shorted out (rubbed raw against the trailer frame). I’m assuming it blew a fuse because I’m getting this error message now too. I’ve checked every fuse under the hood and they’re fine. Could this have blown one of the relays in the fuse box?

 

https://www.tundras.com/threads/2022-tundra-fuse-box-locations-designations.105568/

Look #1 fuse panel

 

Yea box number one is where the parts guy told me to go too. He said the bigger one on the right side “Tow Back up” next to deicer. But that’s a relay. At least it says relay on it…. I’m now wondering if it’s some sort of relay/fuse combo or something

 

Could be, but look at the fuses towards the center row. I see a 30amp tow fuse red that looks interesting but the blue one is the culprit most likely!

 

Did you ever find a solution to this? I am having this issue with my 2024 SR5.

 

Try another 7 pin trailer and see if that solves it. Spent more time on here typing than calling a friend with a trailer

 

I appreciate the enthusiastic response lmao but I’ve already done that, same issue. Also had buddy hook up to my trailer and it works on his. Took it to the dealer and they said there’s nothing wrong, so this is my last resort. Thanks though lol

 

Enjoy your problem. No where did you say " had buddy hook up to my trailer and it works on his." We are only trying to help you

 

Get you a can of this firstly...

$18 Hosa D5S-6 CAIG DeoxIT 5% Spray Contact Cleaner, 5 oz.

https://www.amazon.com/gp/product/B00006LVEU?ie=UTF8&th=1

No matter if this fixes your problem, this is great to have around for maintenance. This may very well be your issue, dirty contacts on the receptacle on your truck. Clean the trailer connector also. Let us know how it goes.


Mike

 

I have this issue too except I'll go from a fully functional trailer to no brakes to me it's a case of too much electronics!!

 

Electronic equipment doesn’t just come and go like that. Electronic connections DO !!!

get that cleaner and do some periodic maintenance.

 

Ugh I'm an computer guy and I'll say you not wrong my point was rather a standalone TBC will just send the intended voltage whenever called on without worrying about every single pin on the connector being 100% I would rather send 12 volts to the brakes regardless of what the truck thinks is appropriate cause if I'm calling for brakes there's generally a good reason.

 

Maybe just get you a standalone TBC then. You will have a new jack wired up on the truck side then. That’s a LOT more work than getting a can of deoxit and spraying connectors, plugging them up and disconnect a few times to cycle the chemicals to clean connections. Not sure what is all so difficult about that.

Do you ever perform periodic maintenance on your computers you maintain?

In today’s world, there is a lot of monitoring current usage and feedback. It’s getting harder to get away from it.

 

and again your missing the point I would argue that the Tundra's TBC is annoying at best and hazardous at worst there's been times that I clean the connections, I have a new pigtail I've inspected the wiring and it doesn't change the fact that if the truck sees any wiring issue while towing the TBC goes into a full error state and won't send voltage to the brakes hence you go from having trailer brakes to effectively not. And then you get to fight with the connections and the truck to get it to work again.

And yes I take care of things computers, truck, trailers etc there's a reason picked Toyota as I tend to maintain and hold onto my stuff for the long term.

 

I most assuredly missed your point. One "feature" I don't like on my truck is the manual override is inactive if in park or foot on the brake. My apology, still do that maintenance though.


Mike