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Electrical Tie into Fuse Box Main Positive?

Discussion in 'Technical Chat' started by BluberryBCtaco, Feb 4, 2024.

  1. Feb 4, 2024 at 1:26 AM
    #1
    BluberryBCtaco

    BluberryBCtaco [OP] Making the magic happen

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    I’m planning to have a Aux panel that has a few LED lights, Compressor, Dash Cam, Backup Cam, and in future a winch.
    The Compressor (35amp) and Winch drawing the most Amps.

    I would like to know if I can tie into the engine bay fuse boxes main positive instead of the battery terminals, as I would like to keep it looking clean.

    If I were to tie into the box, would that cause an issue down or upstream somewhere? IE cable not thick enough etc?

    Im It does feel like this cable goes directly to the battery terminal.

    IMG_6577.jpg
     
  2. Feb 4, 2024 at 4:23 AM
    #2
    deanosaurus

    deanosaurus Caveman

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    I sure wouldn't - electrical capacity aside, you're going to have to chop up the fusebox body to fit another wire in there. You also absolutely do not want to run a winch from that location - the draw, for example, on a Warn Evo 10 is ~350A peak which is almost double what that wire is meant to carry - note the 180A fuse directly below that lug.

    Consider switching to e.g. military style terminals and running a clean pair for your aux panel and a dedicated, appropriately sized run for the winch.
     
    wi_taco likes this.
  3. Feb 4, 2024 at 10:33 AM
    #3
    BluberryBCtaco

    BluberryBCtaco [OP] Making the magic happen

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    Well that’s why I’m asking, to see if it’s viable.

    So that’s a strict no go then? Not even low amperage stuff ie: LED lights, Compressor?
     
  4. Feb 4, 2024 at 10:59 AM
    #4
    MR5X5

    MR5X5 Well-Known Member

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    My $0.02

    If you plan on running a variety of things look into getting a separate relay block to account for individual switching, fuses, wire sizes etc. Feed the new relay block with an appropriately sized, fused, cable directly from the battery.
     
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  5. Feb 4, 2024 at 11:18 AM
    #5
    joba27n

    joba27n YotaWerx Authorized tuner

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    If you have maybe one of two low amperage items like a pair of led ditch lights or a light bar you'll probably be okay but as stated above, if you're running a few things I would recommend installing a separate junction/fuse block and battery feed.

    I have one light bar currently tied in with no issues but i'm thinking of adding a couple more things and in turn am looking into junction boxes to keep things organized with fuses for each circuit.

    I feel it's good practise to avoid tying accessories into OEM circuits as much as possible to minimize issues and ease in diagnosis in the future. Especially if a guy were to forget what he did or were to sell the vehicle to someone that wasn't involved in the installation of said accessory
     
  6. Feb 4, 2024 at 11:29 AM
    #6
    Rock Lobster

    Rock Lobster Thread Derailer

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    I wouldn't. Any cable that ties directly to terminal is going to tuck neatly between the battery and fuse box. Id argue that it's a cleaner way of doing things than trying to booger up the box.

    PXL_20240204_192549453.jpg
     
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  7. Feb 4, 2024 at 8:27 PM
    #7
    Bivouac

    Bivouac Well-Known Member

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    Op it is your vehicle if you decide connecting to the fuse block is the best way go for it.

    Your asking!!

    I hook up any extra electrical loads to the battery . If needed a junction Block to act as a distribution point. With wire size to be more then large enough to carry the highest load and circuit protection as needed.

    Best of luck!
     
  8. Feb 4, 2024 at 8:53 PM
    #8
    BluberryBCtaco

    BluberryBCtaco [OP] Making the magic happen

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    Thank you all for your input,

    I will avoid tie-ing into the fuse box. I will run a aux Distro for all the good things.
    I thought id ask from more wiser and experienced people on here, before I do something stupid and dangerous.

    @Rock Lobster That is actually a wonderful idea of running the aux distro on that wall. Cleaner than having a giant metal plate as i have seen from vendors. Makes working in the engine bay easier.
     
    Rock Lobster likes this.
  9. Feb 4, 2024 at 9:00 PM
    #9
    BLtheP

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    If all the power is going to be grabbed from one source, I would (and did) go straight to the battery and use an MRBF fuse. It’s clean enough, sturdy, and does exactly what it’s supposed to.

    Ignore the terrible red cable showing in the photo, that was preliminary and I was waiting on loom. It’s all done and perfectly clean now but I don’t have a new photo.

    IMG_2936.jpg IMG_2935.jpg
     
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  10. Feb 8, 2024 at 3:22 AM
    #10
    ClassyTacos

    ClassyTacos National Treasure 3, Times a ticking Nickolas

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    Yes you can, it would require a decent amount of work to get it in the fuse box cleanly. You could run straight form the battery terminals down the back of the battery under the fuse box towards the driver fender to what ever Aux Box you chose positioned closer to the driver side firewall. As for relays, depending on the accessories you chose to install the large majority of them will already have a relay and a fuse in the wiring. That eliminates the need for a section of relays. This all depends on if you want to buy the wiring harnesses or if you're one of these bad asses that builds his own harness and power box.

    For us non wiring harness building bad asses--

    Below is a simple way to get what you want in one package. You could also piece it together and buy just the mounting plate. Look around on the web site you might be able to piece it all and save a little.

    Last time I checked the Blue Sea breaker alone was $71 and Blue Sea fuse box $40 on sale from $57.

    https://overlandequipped.com/collec...for-3rd-generation-toyota-tacoma-2016-present

    aux box.png
     
    Last edited: Feb 11, 2024
  11. Feb 10, 2024 at 7:52 AM
    #11
    MR5X5

    MR5X5 Well-Known Member

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    ....and then, one last important thing to consider. The wire from your battery to the trucks relay/fuse box was designed for the trucks specific load. If you go and add what could be a bunch of new load at that point and do not change out the factory wire accordingly, you have just turned the factory lead into a fuse and when that fuse goes you are dead in the water.
     

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