1. Welcome to Tacoma World!

    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 Tacoma discussion topics
    • Communicate privately with other Tacoma owners from around the world
    • Post your own photos in our Members Gallery
    • Access all special features of the site

1996 tacoma main fuse keeps burning, any help appreciated

Discussion in '1st Gen. Tacomas (1995-2004)' started by TacoBurritoSupreme, Aug 12, 2019 at 8:27 PM.

  1. Aug 12, 2019 at 8:27 PM
    #1
    TacoBurritoSupreme

    TacoBurritoSupreme [OP] Well-Known Member

    Joined:
    Mar 14, 2019
    Member:
    #286650
    Messages:
    49
    Gender:
    Male
    First Name:
    Romel
    Vehicle:
    2019 Tacoma off road 4x4
    stock stock stock
    hey guys i need a little help here. my dad has a 96 tacoma pre runner. we were driving in the morning and all the lights went out. then the truck shut off. we waited a couple minutes and returned home. checked everthing and found that the main fuse had blown (ALT 80A)

    replaced the fuse and when returning the positive power back to the battery the connection started sparking and the fuse blew again. checked and made sure everything was off so nothing was powering. just wanted to know where i should start to troubleshoot. and what could of caused the 80a fuse to blow.
    thanks.

    D36A666C-8441-444C-9766-22087591EAE2_zps_9204ba3f650fc8cf5b8ebcd5f3797b1b3b0f0c42.jpg
     
  2. Aug 12, 2019 at 8:44 PM
    #2
    0xDEADBEEF

    0xDEADBEEF Hmmm

    Joined:
    Mar 2, 2019
    Member:
    #285037
    Messages:
    454
    Vehicle:
    2000 4WD MT Single Cab
    Rust, dents, miles.
    You've got a dead short between power and ground somewhere. On my 2000 the manual says that fuse is between the ignition switch and the battery, which doesn't seem very helpful. I think I'd pull the cover on that junction box and start following wires from that fuse. Eventually you'll find some insulation that's scraped off and rubbing against something, probably a body panel or something.

    If you've got a multimeter you can disconnect the battery positive terminal, set it to continuity and put one of the probes in the not-hot side of the blown fuse. Connect the other side to a ground point and i bet the meter will start screaming. Wiggle wires and when the meter goes quiet, you've found where to look. Maybe.


    Edit: clarified battery disconnect
     
  3. Aug 12, 2019 at 8:53 PM
    #3
    TacoBurritoSupreme

    TacoBurritoSupreme [OP] Well-Known Member

    Joined:
    Mar 14, 2019
    Member:
    #286650
    Messages:
    49
    Gender:
    Male
    First Name:
    Romel
    Vehicle:
    2019 Tacoma off road 4x4
    stock stock stock

    Awesome I’ll try that tomorrow morning
     
  4. Aug 13, 2019 at 12:03 AM
    #4
    DrZ

    DrZ Well-Known Member

    Joined:
    Dec 14, 2014
    Member:
    #144262
    Messages:
    1,036
    Gender:
    Male
    Mesa, AZ
    Vehicle:
    96 2.4L 5-speed
    I'm pretty sure all the circuits served by that fuse are also protected by smaller fuses, so it would seem if the short was in one of those sub-circuits the smaller fuse would blow first. What I'm saying is you may have a short in the fuse box itself. I think there have been some threads here recently where the underside of that fuse box was corroded causing shorts or open circuits.

    I'd remove all the other fuses (after taking a picture so I know where they all go). This could help isolate where the short circuit is.
     
  5. Aug 13, 2019 at 12:52 AM
    #5
    Wyoming09

    Wyoming09 Well-Known Member

    Joined:
    Apr 24, 2015
    Member:
    #153833
    Messages:
    6,395
    Gender:
    Male
    New Tripoli Pa
    Vehicle:
    2000 Work truck
    Super Springs
    Just how did you get home??

    With that fuse open the starter will not crank .

    I would look for a shorted Alternator or Starter .
     
  6. Aug 13, 2019 at 12:57 AM
    #6
    robssol

    robssol If it ain't broke, leave it the eff alone!

    Joined:
    Jun 4, 2013
    Member:
    #105622
    Messages:
    7,454
    Gender:
    Male
    First Name:
    Rob
    S. Wisconsin
    Vehicle:
    06 Tacoma, TRD Sport, SR5, 4X4, ACLB
    Frame 2.0, Fog lights anytime, Seatbelt reminder delete, Secondary air filter delete, LED bed lights, Running boards, 2017 Rims, Devil Horns by Andres, Ultra gauge, Cup holder/consol/glove compartment lights, Interior LED conversion, Blue Sea aux. fuse panel, fuse panel mounting plate by Yotamac, ProEFX heated towing mirrors, LED engine bay lights, Redline Quicklift Elite hood struts, Wet Okole Heated Seat Covers, Pop and Lock tailgate theft deterrent mod 2.0, Plasti-dip rear bumper. Decal free visors, Washable cabin air filter, Overhead consol auto dimming override switch, BulletProof Fabricating Skid plate, 2lo module.
    I would put my money on the alternator. Truck quit running:(
     
  7. Aug 13, 2019 at 2:32 AM
    #7
    PilotFerdi

    PilotFerdi Member

    Joined:
    Jul 18, 2019
    Member:
    #299626
    Messages:
    6
    Gender:
    Male
    First Name:
    Ferdinand
    Vehicle:
    2016 Tacoma TRD Sport 4x4 Inferno
    IMHO, it's the alternator. Apologies, Wyoming09, but the starter is powered by the battery, not the alternator. Thus, one can start the engine with a defective starter if there is enough juice left in the battery. Also, the starter and alternator are on separate fuses (see the box).

    The shortcircuit is inside the alternator, between the output connector that charges the battery (and powers the systems), and the ground.

    It's easy to verify:
    1. Disconnect both cables from battery. Fully charge the battery while it's disconnected.
    2. Disconnect the power cable from the alternator. The power cable is a thick, black cable attached to the alternator output by a nut. Your truck might (or might not) have a rubber boot to cover the connector.
    3. Replace the blown fuse (80A).
    4. Reconnect the battery cables to the fully-charged battery; the fuse should not blow anymore.

    At this moment, your truck is powered by battery only. You should be able to turn on the ignition, and start the engine... and the fuse won't blow. The lights should turn on, too. This confirms it's the alternator. Of course, you should not run the engine for a long time without the alternator because you'll deplete the battery.

    Please let me know if my description above it's confusing; I'll try to make it simpler.
     
    Last edited: Aug 13, 2019 at 3:00 AM
    Seagull233 and DrZ like this.
  8. Aug 13, 2019 at 12:41 PM
    #8
    Wyoming09

    Wyoming09 Well-Known Member

    Joined:
    Apr 24, 2015
    Member:
    #153833
    Messages:
    6,395
    Gender:
    Male
    New Tripoli Pa
    Vehicle:
    2000 Work truck
    Super Springs
    I can only guess there is that much difference between 96 and 2000 on the 2000 that fuse feeds the starter relay contacts .

    Not having the 1996 EWD I used what I had as a best Guess.
     
  9. Aug 13, 2019 at 12:56 PM
    #9
    TacoBurritoSupreme

    TacoBurritoSupreme [OP] Well-Known Member

    Joined:
    Mar 14, 2019
    Member:
    #286650
    Messages:
    49
    Gender:
    Male
    First Name:
    Romel
    Vehicle:
    2019 Tacoma off road 4x4
    stock stock stock

    it just turned back on we just dropped it into 2nd and popped the clutch.


    Awesome man, this makes sense i will try when im off of work.
     
  10. Aug 13, 2019 at 5:57 PM
    #10
    PilotFerdi

    PilotFerdi Member

    Joined:
    Jul 18, 2019
    Member:
    #299626
    Messages:
    6
    Gender:
    Male
    First Name:
    Ferdinand
    Vehicle:
    2016 Tacoma TRD Sport 4x4 Inferno
    There's a logical explanation: unless it's completely depleted, a battery will recover some of its charge (it's a physical process called "charge recombination"). How much it recovers is dependent on the health of that battery - newer batteries recover a lot, older ones not so much. In your case, the battery recovered enough to get you going.
     
  11. Aug 13, 2019 at 8:27 PM
    #11
    DrZ

    DrZ Well-Known Member

    Joined:
    Dec 14, 2014
    Member:
    #144262
    Messages:
    1,036
    Gender:
    Male
    Mesa, AZ
    Vehicle:
    96 2.4L 5-speed
    Or the short in the (perhaps) alternator dropped the voltage to the rest of the truck (ECU, ignition, etc.) causing it to stall. Once the fuse actually blew there was no longer a short, so the truck could run off battery power. That is, the rest of the circuits not fed by the 80A fuse had their normal voltage back.
     
    Last edited: Aug 13, 2019 at 10:49 PM
    0xDEADBEEF likes this.
  12. Aug 14, 2019 at 3:27 PM
    #12
    PilotFerdi

    PilotFerdi Member

    Joined:
    Jul 18, 2019
    Member:
    #299626
    Messages:
    6
    Gender:
    Male
    First Name:
    Ferdinand
    Vehicle:
    2016 Tacoma TRD Sport 4x4 Inferno
    That could be, too.
     
  13. Aug 15, 2019 at 10:03 AM
    #13
    TacoBurritoSupreme

    TacoBurritoSupreme [OP] Well-Known Member

    Joined:
    Mar 14, 2019
    Member:
    #286650
    Messages:
    49
    Gender:
    Male
    First Name:
    Romel
    Vehicle:
    2019 Tacoma off road 4x4
    stock stock stock
    Alright guys i ran all the tests, and turns out the alternator had gone out. so im taking it to a shop to make sure their isnt any other type of electrical issues. thanks guys for the help, would of spent weeks trying to figure it out otherwise.
     

Products Discussed in

To Top