2018 Tundra TRD Trailer not connected warning

Those of you with 2018s who have installed p3s: how did you do it? I have not been able to find a 2018 tundra harness adapter anywhere online; they are all 2017 and below. Did you splice it in, or is there a harness I haven’t run across?

 

Triple check your trailer wires!! Seriously.

Stock brake controller, brand new trailer from factory (Carry-On, 9900lb rating, dual axle with brakes on all 4)

Worked....meh...OK for the first few trips. Controller set to 10 on an empty trailer (about 2300lbs) would just baaaaaaarely lock some brakes up. I.e., OEM controller sucks. Then, suddenly...no trailer connections. Got power, brake lights, signals....no brakes.

Ran through the trailer. Nothing I could see wrong. Tested wires—good to go.

Brought truck to dealership; they ran the check in the IBC ECU. It was toast.

Got a new IBC via warranty. (Upgraded version?). Hooked up trailer and it “kinda” worked. Could only set gain to 2.5 max before the controller would make a bunch of clicking noise and then flash the error on the dash.

Tore apart trailer again, this time pulling wheels, brakes etc etc. Everything looks OK.

Disconnected truck battery in hopes that the new IBC ECU just needed to be part of a system reset.

No dice!

So, third time back into the trailer. It HAS to be an issue somewhere there...annnnnnd sure enough.

Apparently, some random wire was routed by the factory UNDER THE U BOLT CONNECTING AXLE TO TRAILER!!! The wire got pinched and severed, but still made occasional contact via the axle housing.

Repaired the wires. Can’t set new IBC to more than 3.5 empty right now. It’ll lock those trailer brakes up and very noticeably stops the truck. I don’t like how the IBC seems to be “all or nothing” and have a new P3 controller on the way.

But lesson learned. Triple check the wires!!!

 

I had my trailer inspected twice now by a credible trailer mechanic, and still the IBC will not work. I'l have to see if a new one will fix it, otherwise I'll get the p2 installed

 

Yeah. It’s frustrating.

 

Our last two camping trips got snowed out, so I didn't get to tow my trailer with my 2018 before we had to shut down the trailer for the winter. So, I didn't get to find out if my truck was going to have the same problem. I am hoping that if it does, Toyota has figured this shit out by May 2019 when it's time to go camping again.

 

My 2018 Tundra is at the dealer right now for trailer brakes not working while traveling home from a recent camping trip. About half way home, the truck alerted me that the trailer has been disconnected. Then it reconnected and disconnected several more times before finally staying disconnected. All the lights on the trailer worked, but no brakes. My dealer told me Toyota is aware of the issue and just had a meeting yesterday on how they plan to deal with the problem. I'm expecting a phone call tomorrow. I'll post when I hear something.

 

Thanks for the heads-up, MYo. Something to look forward to, NOT! I'd read where the "trailer not connected" issue was corrected before my truck was built (mid-May 2018). I've towed five times with no issue. Fingers crossed, but I'll be on the lookout.

 

I have had a busy week unpacking. I am calling Toyota this week about it. I think I may tell them to install my aftermarket controller if they cannot get their act together. Their truck is amazing in all other regards.

 

Thanks for posting and please give us an update when you hear.

 

The dealer kept my Tundra for about a week...with no answers. The dealer said they were waiting for a phone call from Toyota on how they plan to fix this issue. It's been 2 weeks and still no new information. The dealer is Aubrey Alexander Toyota in Selinsgrove, PA. I'll post when I hear something. I plan to call tomorrow (Monday).

 

This is a KNOWN and widespread issue with both 2018 AND 2019 Tundra’s integrated brake controller. I have talked to dealership, regional, and corporate and they literally don’t know how to fix it or even work around it. Since my truck is only 30 days old I have considered envoking the lemon law since this is a piece of safety equipment, but trying to work with the dealer first because they should at least get a shot at saving my loyalty.

Pretty disappointed that Toyota is not issuing a recall because they KNOW it is an issue. I guess that is what I get for 30 years of loyalty?? Everyone should test their Tundra’s ASAP especially if the are new and covered under your states lemon law and then take it to the dealer and then issue a claim

 

I'm taking the same approach...trying to let the dealer figure it out first before taking this to another level.

 

Exact same issue with my 2019!! WTF???? Serious safety issue IMO

 

I am currently sitting at a dealership waiting on a regional tech to look at the problem, originally I just had the disconnect issue but now all lights and aux work fine, but no trailering breaks. This is the 3rd time I've come in, this time with my trailer at their insistence.

 

I've been dealing with the same issue. 16' tandem axle trailer with trailer brakes (carrying two 4-wheelers). After applying brakes several times while driving, these warning lights come on and the trailer brakes stop working. I have video also but couldn't get them to load. The owner's manual says if you're getting these symbols, the trailer brake controller is overheating and to take the truck to the dealer. I contacted Toyota Corporate and they had me take the truck in with the trailer. The dealer advised there is no problem with the truck and everyone having this problem has something wrong with their trailers. I took it to Legends Toyota in KCKS three times and Jay Wolfe Toyota in KCMO once and they all say the same thing. The funny thing is, the first time I checked in at both dealerships, the service advisors both stated, "they've seen this before and it should be simple to fix." I've dealt with the regional tech and corporate three separate times now. When I explained I hooked this trailer up and towed with two Ram 2500's without issues, they shrug their shoulders and say "Toyota computers are more sensitive." During the third contact with the corporate case manager, she stated there was nothing else they could do and they were closing the case. My truck now has 12k miles on it and I don't want to void the warranty by hard-wiring an aftermarket brake controller. It seems no one makes an adapter yet for the new plug under the dash.

 

Hello All,

New member, first post. My 2018 Crewmax with tow package had the same issue, always giving me the "no trailer connected" message.

I first went to a local RV dealer and spent money. They found nothing wrong with the travel trailer. It's a 2013 with LED brake lights. Then to the Toyota dealer twice (Village Toyota in Homossasa Springs, FL). They kept saying (again and again) that it was the trailer. By the way I forwarded this email thread to the Tech Supervisor.

Yesterday I went to Walmart, bought the Sylvania Load Equalizer ($15.00), and installed it as previously mentioned in this thread. Bingo!! Now the IBC works great, no more "no trailer connected" message. The trailer brakes work fine, and all lights on the trailer work correctly, too.

Thanks so much for the info on this problem that others have previously posted! My Tundra now works as it's supposed to. I'm not a knowledgeable electrical person by any means but I was able to figure out how to connect the load equalizer.

Merry Christmas to all.

 

I had this issue on my 2016 tundra. All the lights on trailer worked, IBC read and activated the trailer brakes but once on the road, I lost connectivity and electric brakes on trailer.
The connection on the truck was not accepting the mail end on the trailer and had to tie the plug to stay in place on the truck for the rest if the trip. Even after the quick fix the electric brakes were spongy and just didnt feel right using the IBC on the truck.

After trip, took truck to dealer (January 2018) and they said truck was fine and to bring in trailer.
F*** that. Didnt want to deal with bringing in my 25ft enclosed trailer to dealership. They said I could take to another dealership. But screw that.

Trailer was fine since it's been towed fine for 5 years on my brothers 2004 super duty.
Bought a P3 brake controller and no regrets.

Clean and simple install, and very responsive. PLUS love the "breaking boost" that comes on the P3.
For those unfamiliar, the "boost" is activate electronically when you slam on your truck breaks suddenly. The P3 automatically activates the "boosts" and gradually increases the electronic breaking level from what ever setting you have it set, all the way to maximum in the event of a sudden/abrupt stop.

 

Hello everyone I just got new Tundra 2018 production date 8/18 and having the same issue with my new travel trailer 2019 .
I also have other cargo trailer 2016 no problem with the brake. I had Toyota checking my Tundra they said all good
I had the dealer for trailer replacing my brake sys on the new trailer and still having issue
Thanks to you for all the info now I know it's my Tundra.

 

Belated welcome from NY.

 

Welcome from NY.

 

I have the same problem, "trailer disconnected" warning with my brand new 2019 TRD Pro. However, it gives the warning, and then a few seconds later it seems happy again, and the controller sees the trailer. But then a few minutes later I get the disconnect warning again. This cycles repeats. Here's a short video I made.

Has anyone heard if there is now an official Toyota TSB so I can call my dealer about it?

 

Update on my tundra 2018 5000 miles
My dealer did update for the brake controller computer. After update I checked and still having problem contact Toyota customer service we've been going on and off about the situation. the other day I tow the trailer again very short drive about four Mile and it was okay I'm still needs to check it for a longer ride to see if he got fixed or not but I can tell you one thing it's only happened on a single axle trailer with a brake controller I tow 3 trailes wwith double axle and it was no problem.

 

The resistance of a single typical electric brake is in the 3 to 4 ohm range. If you have two electric brakes (single axle) they are wired in parallel, so you get half of that. Meaning, 1.5 to 2 ohm resistance that the brake controller sees. Source: https://www.etrailer.com/faq-testing-trailer-brake-magnets-for-proper-function.aspx. Now if you put a 6 ohm load equalizer resistor in parallel with your brakes (which is what this thread is about) you achieve two things, neither of which I think is a great idea.

1) You lower your total resistance that the brake controller sees by 25%. (6 ohms in parallel with 2 ohm is a net resistance of 1.5 ohm). Meaning, the brake controller has to supply 25% more current to get the same braking power. Maybe that is fine, and the brake controller can handle it, I don't know.
2) 25% of the current from your brake controller goes through your 6 ohm resistor, and heating that up. If we assume 12V coming out of the brake controller, that is 2A, resulting in 12W being put in the equalizer resistor. Make sure that thing is sized for that.

This is a long way of saying, try a higher resistor value, as WAtundra4x4 also suggested. So i went with 30 Ohm, and that works fine. No more trailer disconnect! Here's

$11 uxcell 2 Pcs Aluminum Clad Wire Wound Resistors 25W 30 Ohm 5%

the part. Of course, now maybe WAtundra4x4 is right, and we can go much higher. That would be nice.

 

Well, I just bought a 2019 and also bought a brand new single axle TT. My truck would not connect to the trailer. I am scheduled to leave on a 7-day camping trip and didn't have time to go back to the dealer, so in a pinch, I installed the 6 Ohm resistor (that's all they had at the auto parts store) and it now detects the trailer and the brakes work. When tested, however, I couldn't get the trailer to lock-up with gain at 10. I laid on the brakes going down a big hill and the resistor was cold to the touch when I stopped a few minutes later......

I do have an appt at the dealer set-up after the trip.

 

Fish, two Suggestions:

1) Not all trailers necessarily can lock up their brakes. It depends on the quality of the electric brakes.
2) You can put multiple of those 6 ohm resistors in series, so that more current is going to the brakes instead of the resistor.

Have fun on the camping trip!!

 

So I am interested in this additional bit of info from users here: has anyone experienced this with double axel TTs? I wonder if this is limited only to single?

 

I had this problem with a dual axle enclosed trailer, seemed to be that the physical connection was intermittent. If I carefully secured the cable it wouldn't disconnect.

 

I concur with TundraPro2019 math and solution. I believe his solution is better than the 6 ohm resisters.

 

my 2019 was displaying "trailer disconnected" messages the last time i towed my flat bed, and now it won't recognize the trailer at all. one local dealer is aware of the issue and waiting on a TSB from Toyota, but has no idea when it's coming. supposed to be towing from CA to UT later this week, too...

EDIT: spoke to someone about this and it sounds like there is a TSB as of April 1st: T-SB-0036-19. going into the dealer tomorrow with that information, will report back