1. Welcome to Tundras.com!

    You are currently viewing as a guest! To get full-access, you need to register for a FREE account.

    As a registered member, you’ll be able to:
    • Participate in all Tundra discussion topics
    • Transfer over your build thread from a different forum to this one
    • Communicate privately with other Tundra owners from around the world
    • Post your own photos in our Members Gallery
    • Access all special features of the site

2020 Tundra - Brake Controller

Discussion in '2.5 Gen Tundras (2014-2021)' started by eliblackburn, May 11, 2021.

  1. May 11, 2021 at 8:06 AM
    #1
    eliblackburn

    eliblackburn [OP] New Member

    Joined:
    May 10, 2021
    Member:
    #62878
    Messages:
    4
    Gender:
    Male
    First Name:
    Eli
    Vehicle:
    2020 Tundra TSS
    Hi! New to the group, but been reading lots of great info on here last couple of weeks.

    We bought a new travel trailer a couple months ago and have experienced weak braking on the trailer. At first I thought it was the trailer and even replaced all 4 brake assemblies, but still got weak braking power. The other day I severed the blue brake wire on the backside of the harness just behind the rear bumper of my truck. With my trailer plugged in and gain all the way up to 10 I only got about 11 amps on my multimeter. I then tested the individual brakes on the trailer and got about 2.8 amps. It's a dual axle trailer with 10" brakes on all 4 wheels, so the 2.8 times 4 adds up to about 11 amps which is what I got on the truck output. From my research each brake should get 3.2-4 amps and the truck should put out a max of 16 amps at full gain. So I took my truck to Toyota for the second time. After a few hours the tech called me and said it checks out to factory specs and 10 amps is about the max output for the electric trailer brake controller. He said Tundras prior to 2012 would put out close to 20 amps, but later models were only rated for 10 amps. Sounds like Toyota has messed this up! My trailer is only 5,000 lbs so well below the towing capability of a Tundra, but it doesn't supply enough power to properly brake a dual axle trailer.

    I just ordered a Teknosha P3 brake controller to see if that will correct the issue and supply enough current to the trailer brakes. The Tekonsha website and other sites like etrailer say the P3 isn't compatible with a 2020 Tundra but I called tech support at Tekonsha and the guy said they have notes in their system from people saying it does work but it's just not published yet. He said get the 3031-P wiring harness and that should plug right into my Tundra to connect the P3. Fingers crossed this works!

    If it works I'm going to ask Toyota to reimburse me for the after market brake controller.....
     
  2. May 11, 2021 at 8:44 AM
    #2
    timsp8

    timsp8 Member

    Joined:
    May 11, 2018
    Member:
    #15231
    Messages:
    3,317
    Gender:
    Male
    First Name:
    Tim
    NY
    Vehicle:
    2018 Tundra Limited Crewmax
    Did you check with Toyota first? There was a TSB that some said helped, even on new models. There’s a couple of threads about it.
     

    Attached Files:

  3. May 11, 2021 at 11:28 AM
    #3
    JohnLakeman

    JohnLakeman Burning Internet Daylight

    Joined:
    Feb 21, 2019
    Member:
    #26430
    Messages:
    3,008
    Gender:
    Male
    Outside of Weird, TX
    Vehicle:
    2017 MGM DC TSS 4.6L
    TRD Pro grille, 2018 LED Headlights, Undercover Flex bed cover, Neoprene seat covers, Bed/tailgate mats, Power tailgate lock, auto headlights, illuminated key switch
    Not an uncommon problem.

    Tekonsha guy is close, but the 3031-P is not a plug-n-play harness for 2018+ Tundra, only for 2015?-2017. In fact, for maximum economy, you could probably just extend the wires of the universal harness that comes with P3 and forget the 3031-P harness.

    The harness connector used to hard wire an aftermarket controller is on the passenger-side upper dash/firewall (2018+). You'll have to extend the blue (controller output) and black (12V+) wires to reach. Use Search to find a ton of threads by owners replacing the IBC with aftermarket controllers. If you can't find anything useful, shout out.

    Your next question after installing the P3 will be: "How do I stop my Tundra from telling me I don't have a trailer connected, when I don't even have the IBC anymore?" Do the Search.

    Oh, uh, good luck getting Toyota to refund your money for the P3. :D
     
  4. May 11, 2021 at 12:01 PM
    #4
    eliblackburn

    eliblackburn [OP] New Member

    Joined:
    May 10, 2021
    Member:
    #62878
    Messages:
    4
    Gender:
    Male
    First Name:
    Eli
    Vehicle:
    2020 Tundra TSS
    Thanks for the info! The P3 should be here today so I'll try to get it installed tomorrow. Annoying that Toyota can't figure this issue out!
     
  5. May 11, 2021 at 12:13 PM
    #5
    Tundra234

    Tundra234 New Member

    Joined:
    Nov 30, 2018
    Member:
    #22402
    Messages:
    11,440
    Gender:
    Male
    First Name:
    George
    Florida
    Vehicle:
    2020 Tundra DC SR5 Barcelona
    Alot of them
    His is a 2020 and the TSB was for 2016-17, but that doesn't mean Toyota corrected it. They are still using the old gray sealant for the cam towers instead of the black sealant. :notsure:
     
  6. May 11, 2021 at 4:05 PM
    #6
    timsp8

    timsp8 Member

    Joined:
    May 11, 2018
    Member:
    #15231
    Messages:
    3,317
    Gender:
    Male
    First Name:
    Tim
    NY
    Vehicle:
    2018 Tundra Limited Crewmax
    Yeah but I’ve seen posts where 20/21 owners got theirs fixed by this or another tsb. I don’t feel like searching though.
    Did Toyota diagnose it? What did they tell you when they said they couldn’t figure it out?
     
  7. May 12, 2021 at 6:29 AM
    #7
    eliblackburn

    eliblackburn [OP] New Member

    Joined:
    May 10, 2021
    Member:
    #62878
    Messages:
    4
    Gender:
    Male
    First Name:
    Eli
    Vehicle:
    2020 Tundra TSS
    Yes Toyota did say they diagnosed it. I had it in there twice in the last week. The guy said per factory specifications after 2012 the Tundra has only put out approximately 10 amps max from the IBC. He said there was no fix for it, but I didn't know then to ask about this TSB thing. My new P3 controller arrived yesterday though so I'm going to install that and see what happens. Sounds like it is a far superior brake controller and I'm going to be towing a lot so might be worth it anyways. I'll update here once I install it.
     
  8. May 12, 2021 at 6:50 AM
    #8
    Vizsla

    Vizsla ☠️☠️☠️

    Joined:
    Jul 14, 2016
    Member:
    #3867
    Messages:
    2,305
    There was no IBC for 2013 or earlier.
     
    NewImprovedRon likes this.
  9. May 12, 2021 at 7:31 AM
    #9
    timsp8

    timsp8 Member

    Joined:
    May 11, 2018
    Member:
    #15231
    Messages:
    3,317
    Gender:
    Male
    First Name:
    Tim
    NY
    Vehicle:
    2018 Tundra Limited Crewmax
    Let us know how it goes. There’s also a mount for a P3 that fits where the stock controller was.

    https://www.esptruck.com/product-page/p3-brake-controller-mounting-kit
     
    JohnLakeman likes this.

Products Discussed in

To Top