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2017 Tundra Tow Plug - no tail lights?

Discussion in '2.5 Gen Tundras (2014-2021)' started by laltaffer, Jan 9, 2021.

  1. Jan 9, 2021 at 12:02 PM
    #1
    laltaffer

    laltaffer [OP] New Member

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    So maybe my memory is wrong but using the 4pin connector I would swear that I used to get taillights working on my trailer - currently only brake and turn signals are working.

    To troubleshoot I bought a tester, and then bought a new 7/4pin plug. An OEM part. But still no tail lights when I connect the trailer and turn on my lights. My truck tail lights work, but seems like the signal isn't being passed down through the plug.

    Any ideas? Anything I should check? Do I just go to a dealer now?

    I don't like doing long trips with the trailer knowing the tail lights aren't working.
     
  2. Jan 9, 2021 at 12:12 PM
    #2
    AZBoatHauler

    AZBoatHauler SSEM#140 / 2.5 gen plebe

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    2017 CrewMax 4x4, 2017 LandCruiser, 2005 Sequoia 4x4
    Demello / SOB Fab Bumpers, SuperWinch, WKOR sliders, RCI skids, Baja Designs lighting, Billy 6112 and 5160 w/ CB +2, JL Audio with Alpine HU, DD 10" Exhaust, LED headlights, Rago fab mounts, 35” BFG, HAM radio
    See if you have voltage with your headlights on at the 11 o’clock pin on the 7 pin connection. Or the pin that feeds the brown wire on the 4 pin.

    ETA if you’re under warranty the dealer is a fine choice as well.
     
    laltaffer[OP] likes this.
  3. Jan 9, 2021 at 12:18 PM
    #3
    frichco228

    frichco228 Valued Member

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    Eibach Pro Truck Stage 2 suspension, HD RAS, 285/75-18 Nokian Outpost AT, LoPro bed cover, TRD rear sway bar, DD 10 inch exhaust, and various other goodies
    Check your fuses too in case you have not.
     
    laltaffer[OP] likes this.
  4. Jan 9, 2021 at 12:19 PM
    #4
    Ckatz53

    Ckatz53 Newish

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    www.fouroneodetailing.com
    Having this same issue as well with my 6x10. They worked initially, but in the past 3 months have gone out. I can't track down the issue. Don't think it's a trailer issue as it is only a year old. Brakes/turn signals work just no running lights on the trailer. Haven't gotten around to testing the voltage at the truck's connector.
     
  5. Jan 9, 2021 at 12:23 PM
    #5
    laltaffer

    laltaffer [OP] New Member

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    I'll check those items. One thing I should mention is that I started this DIY fix by fully re-wiring my trailer since it had been through a lot and it was easy enough. But it didn't change anything. I'll check the fuses in a few minutes, but don't have a way to check voltage right now. Will look to see how I might be able to get that done
     
  6. Jan 9, 2021 at 12:27 PM
    #6
    AZBoatHauler

    AZBoatHauler SSEM#140 / 2.5 gen plebe

    Joined:
    Aug 13, 2019
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    #34576
    Messages:
    7,940
    Gender:
    Male
    First Name:
    Adam
    So.Arizona
    Vehicle:
    2017 CrewMax 4x4, 2017 LandCruiser, 2005 Sequoia 4x4
    Demello / SOB Fab Bumpers, SuperWinch, WKOR sliders, RCI skids, Baja Designs lighting, Billy 6112 and 5160 w/ CB +2, JL Audio with Alpine HU, DD 10" Exhaust, LED headlights, Rago fab mounts, 35” BFG, HAM radio
    This
    Katzco Voltage Continuity and Current Tester - 6-12 V DC - 24 V AC Circuit - Heavy Duty - Long Probe Tester With Indicator Light - 54 Inch Cord for Low Voltage Systems, Cars, Live Wires, Fuses https://www.amazon.com/dp/B01BGZ9XRS/ref=cm_sw_r_cp_api_glc_fabc_EgH-FbQVX5NXM

    or one of these

    AstroAI Digital Multimeter with Ohm Volt Amp and Diode Voltage Tester Meter Continuity Test (Dual Fused for Anti-Burn) https://www.amazon.com/dp/B01ISAMUA6/ref=cm_sw_r_cp_api_glc_fabc_zfH-Fb3N0382M
     
    laltaffer[OP] likes this.
  7. Jan 9, 2021 at 12:31 PM
    #7
    laltaffer

    laltaffer [OP] New Member

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    Thanks!
     
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