2017 Integrated Brake Controller

2017 Tundra SR5 4x4 CrewMax

My IBC at a Gain of 10 doesn't even come close to locking my 2022 travel trailer's brakes. All I get is bare minimum braking.

Hook it to a friend's 2015 F150 and good braking at Gain 3 and locks the wheels at Gain 5.

So I removed the factory IBC and installed a Tekonsha P3 with the matching dash panel and vehicle specific wire harness adapter. At a Gain of 14 and using B1, B2 and B3 and without boost, no better than the factory IBC.

At my last oil change, I had Toyota check on the software updates and my IBC and the whole truck has all of the latest updates.

What should I inspect next?

 

One of the threads on here mentioned the truck not getting the correct voltage from the trailer. I think they put a resister in the wire to fix it. Search for that thread or check voltage at the 7 pin adapter to see if it’s getting the right #s.

 

I would check that your wiring from the IBC to rear of the truck. Sounds like wire issue or dirty connections. Is you plug connecting tightly, I have a friend ask me to pull his cannon trailer to an event, the plug would not stay in, but works great on his Chevy.

 

You ever get this figured out?

 

No. A couple months later, the truck began to intermittently recognize the trailer was present. Then the truck would give an intermittent warning there was a wiring problem and it would disable the trailer brakes. Nothing more fun going down the road on a trip on a 6% downgrade and that's when it decides to short out leaving you with no brakes. The issue went from very intermittent to nearly constant after that; 9 out of 10 brake applications would result in a short.

I had my trailer checked out by the dealer. No problem with the trailer brakes. They hand checked all the wiring and magnets. I drove around with them in their Chevy Silverado and the trailer brakes worked fine; not a single error message. I had the dealer check my truck with their emulator; yep, immediate fault found.

I swapped out the OEM IBC for a Tekonsha P3 and connected it to the truck with their wiring harness adapter; immediately gave an error message when braking of an over current/short circuit condition.

I took the truck to Toyota. After a week there and a lot of money for diagnostic fees, all they could do was tell me they don't know. They hand checked all the wiring underneath from the 7-pin, over the spare tire, down the passenger side frame rail, up into the engine compartment, into the power distribution box, out of the box and to the bulkhead connectors into the passenger compartment etc etc and found no problems. They ran all of the computer diagnostics which gave no errors. But as soon as you plug the emulator in, yep, short circuit. Their only suggestion was to throw parts at it. A new IBC, a new wiring harness under the truck, pull the dash and replace the interior wiring harness, replace the brake pedal and other brake wiring which also runs to the ABS, etc. etc. Parts are seriously expensive and my dealer's labor rate is now at $200/hour! I could easily drop $5,000 and still not have the problem solved; screw that.

So I removed the OEM IBC and installed the Tekonsha P3 independent of the truck's wiring which solved the problem.

And that really pisses me off as I bought a truck with an integrated IBC for a reason. Now I have to look down to where my knee is to read the P3 screen instead of having the information neatly displayed up in the instrument cluster.

I have since filed a NHTSA compliant with all my documentation. I don't expect to hear anything back. But I did find upwards of 50 similar NHTSA complaints from just 2016 and 2017 on the exact same issue. And in each of those complaints, the owner said Toyota could not figure out the problem and had no solution.

 

66lincoln I have a 2017 Crew Max Tundra with the original IBC. I have a Tekonsha P3. I disconnected the original IBC and connected the Tekonsha P3. Started my truck and the dash said "go to the dealer, brake controller ...". Did your truck have a Toyota IBC installed? When you say you "installed the Tekonsha P3 independent of the truck's wiring which solved the problem." What exactly did you do? I know there are 4 wires, Blue goes to the trailer 7 pin connector. What did you do for the other three wires? Did you have to have the IBC "erased" from the truck computer? Your help will be greatly appreciated.

 

66lincoln I have a 2017 Crew Max Tundra with the original IBC. I have a Tekonsha P3. I disconnected the original IBC and connected the Tekonsha P3. Started my truck and the dash said "go to the dealer, brake controller ...". Did your truck have a Toyota IBC installed? When you say you "installed the Tekonsha P3 independent of the truck's wiring which solved the problem." What exactly did you do? I know there are 4 wires, Blue goes to the trailer 7 pin connector. What did you do for the other three wires? Did you have to have the IBC "erased" from the truck computer? Your help will be greatly appreciated.

 

Probably not a solution for you, but thought I would comment on my experiences. I, too, have a '17 that had issues with the IBC. I had my dealer update the software per the TSB. It greatly helped. I tow a 16 foot tandem utility trailer with a 5k tractor. After the update my brakes responded a lot better, but not what my other truck would do with the P3.

I have found electric over hydraulic mode gave the best braking performance. I will say that my trailer has non-self adjusting brakes. After I adjusted them, the voltage need was considerably less. I think 3.5 is all that was needed to just about lock up my trailer, towing my tractor. Good luck on your quest!