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1st Generation Toyota Tacoma (2003) Left Rear Tail Light Wiring Diagram

Discussion in '1st Gen. Tacomas (1995-2004)' started by testelle, Nov 1, 2019.

  1. Nov 1, 2019 at 7:06 AM
    #1
    testelle

    testelle [OP] Well-Known Member

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    This is literally just a free information posting that I'm trying to put up in good will to fellow 1st gen. Tacoma community folks. I was wiring a truck cap and was trying to scour the internet for what should have been a quick look as to which wires to splice for the 3rd brake light on the cap. You'd think that would be easy to google, huh? Couldn't find it on google or youtube so I'm posting it here for future people.

    I'll post a pic in a minute from my phone, but its easier to type on the desktop computer.

    Please feel free to correct me if I'm wrong here, but my cap's 3rd brake light is working so I at least have those two wires right (ground and brake).
     
    Ben Benson likes this.
  2. Nov 1, 2019 at 7:12 AM
    #2
    testelle

    testelle [OP] Well-Known Member

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    [​IMG]

    That's the first gen wiring harness to the driver side taillight.

    Going upper left position (as seen on pic) clockwise around it. Black/white is ground. Double solid green as flashers/hazard. Double green w/ black as left turn. Double green w/ white is brakelight. Double Black/red is backup. Single green is running light.

    So I spliced the he Black/White wire and the Green/white to the 3rd brake line from the truck cap. It worked.
     
    lightnfast and cruiserguy like this.
  3. Nov 1, 2019 at 11:39 AM
    #3
    nzbrock

    nzbrock Well-Known Member

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    SAW 2.0 Coilovers Wheeler's 5 Leaf + 3 AAL Bilstein 5100s LCE long tube header Flowmaster Delta 50 Muffler FJ Trail Team Wheels 255/85/16 Cooper ST Maxx 4Runner overhead sunglass console 4Runner leather seats All LED lights Red/Clear Tail Light Tundra Brakes HID Projector Retrofits 4Runner Auto Up/Down Windows Bullet Liner Cargo tie down system E-locker axle swap w/4.56 Gears ARE MX Cap Prinsu Toprac Custom heated turn signal/puddle light mirrors Volant Intake Tube
    You actually need 4 different diagrams for the entire tail light assembly: Taillight and Illumination, Turn Signal and Hazard Warning Light, Stop Light, and Backup Light.
    You also tapped into your trailer harness jumper (which is a good thing) instead of the stock wiring. That's why you have double wires.

    I've attached all 4 wiring diagrams to this post. These will work for all 01-04 trucks, 95-00 is slightly different with the location of a ground.
     

    Attached Files:

    cruiserguy likes this.
  4. Nov 1, 2019 at 7:25 PM
    #4
    testelle

    testelle [OP] Well-Known Member

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    Yup... those were the same FSM diagrams I referenced that lead me to decide what to tap.

    Btw... could you define "trailer harness jumper" because the mess of mostly green between my fingers IS the OE wires that clips directly into my tail light. Thats what I originally unplugged in the first place to add the trailer harness. You can see the trailer harness plugged into the factory plug (dangling down with the yellow, white, brown wires).
     
  5. Nov 1, 2019 at 7:42 PM
    #5
    nzbrock

    nzbrock Well-Known Member

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    Oh you’re right about the trailer harness. That’s my mistake. The double wires must be going to the other taillight. That’s one of the differences between 01-04 and 95-00.
     
    testelle [OP] likes this.
  6. Nov 2, 2019 at 1:21 AM
    #6
    Wyoming09

    Wyoming09 Well-Known Member

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    Soldered and heat shrink ??

    If not the first application of Liquid brine in a few days it will no longer be working.

    That stuff gets in every place
     
  7. Nov 2, 2019 at 6:17 AM
    #7
    testelle

    testelle [OP] Well-Known Member

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    Yes sir! Soldered and heat shrinked. Was my first time doing that.
     
  8. Nov 19, 2019 at 8:51 AM
    #8
    RaceRedFiveOh

    RaceRedFiveOh New Member

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    Not to thread jack, but I can't get my passenger side running light to work. The brake light works fine, and I've replaced the bulb. Driver side everything is all good.

    If I'm reading the diagrams correct, green wire goes into pin #2 on drivers side, leaves from pin #6 to travel to passenger pin #2. I saw another thread, someone had said the spade connector had corroded. Are these plugs replaceable or rebuildable?

    Can I just tap a wire off the green feeding driver #2, and route that over to #2 on passenger? Is there a need to travel through the connector?
     
  9. Nov 19, 2019 at 11:46 AM
    #9
    testelle

    testelle [OP] Well-Known Member

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    Interesting questions. Sorry, I'm definitely not a mechanic. My goal was to provide an easy resource above to show someone what wires to tap for wiring their truck cap since I scoured the internet fruitlessly.

    Not sure?

    Try it and see?

    Yeah, sorry.
     
  10. Nov 19, 2019 at 1:30 PM
    #10
    Wyoming09

    Wyoming09 Well-Known Member

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    Time to break out your Meter and find the problem.

    Sockets corrode

    it is possible to get the bulb in wrong

    You can repin any of the Toyota Plugs if you can get the correct parts.

    If your doing Electrical work the best thing is to have a copy of the Electrical wiring diagrams for your vehicle .

    I won`t do electrical work without it .
     
  11. Nov 22, 2019 at 2:59 PM
    #11
    Arctic Taco

    Arctic Taco Serenity-the Arctic Taco, another slow build

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    Check your ground, seems like that is a common drama for 12v DC, especially in northern (rust promoting areas)



     

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