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

Two wires from my negative battery terminal

Discussion in 'Technical Chat' started by HuckleSmothered, Nov 13, 2011.

  1. Nov 13, 2011 at 5:18 AM
    #1
    HuckleSmothered

    HuckleSmothered [OP] Member

    Joined:
    Nov 9, 2011
    Member:
    #66740
    Messages:
    21
    Gender:
    Male
    Vehicle:
    95 Tacoma Ext Cab
    I have two wires running from my negative battery terminal. One is the heavy four gauge one. The other is a small one that runs about three inches right to the frame next to the battery.

    I'm worried about it since it is not connected well. The battery is a bit short and doesn't lock well into the battery tray (just bought the truck and it was already like this). It slides around a bit and the short, small gauge wire got ripped off.

    Since buying the truck, I've had the check engine light come on twice. After the first time, it was because I had blown a fuse that was for the OBD sensor. Coincidentally(?) the small wire was disconnected. I reconnected it and a day or so later the light came on again. The battery had slid and disconnected the smaller wire again. I don't know if they are related.

    Can someone shed some light on my battery wire issue? Is this second, smaller wire from the negative battery terminal important (not talking about the main negative wire)? Could it be the cause of my check engine light.
     
  2. Nov 13, 2011 at 6:22 AM
    #2
    HuckleSmothered

    HuckleSmothered [OP] Member

    Joined:
    Nov 9, 2011
    Member:
    #66740
    Messages:
    21
    Gender:
    Male
    Vehicle:
    95 Tacoma Ext Cab
  3. Nov 13, 2011 at 6:23 AM
    #3
    98tacoma27

    98tacoma27 is gooder 'en chicken Moderator

    Joined:
    Dec 18, 2008
    Member:
    #11714
    Messages:
    49,813
    Gender:
    Male
    First Name:
    Ben
    Beech Creek
    Vehicle:
    05 Tundra SR5 (+250k AND COUNTING), 88 SR5 PU (SOLD), 98 TRD OR (CRUSHED)
    5100's all on fours
    Can you get the code read? And I have never heard of an ODB/OBD sensor.
     
  4. Nov 13, 2011 at 6:25 AM
    #4
    98tacoma27

    98tacoma27 is gooder 'en chicken Moderator

    Joined:
    Dec 18, 2008
    Member:
    #11714
    Messages:
    49,813
    Gender:
    Male
    First Name:
    Ben
    Beech Creek
    Vehicle:
    05 Tundra SR5 (+250k AND COUNTING), 88 SR5 PU (SOLD), 98 TRD OR (CRUSHED)
    5100's all on fours
    To add, yes it is important.
     
  5. Nov 13, 2011 at 6:31 AM
    #5
    wikid

    wikid Well-Known Member

    Joined:
    Oct 22, 2011
    Member:
    #65630
    Messages:
    74
    Gender:
    Male
    Tempe
    Vehicle:
    FJ
    That wire is important. Body ground
    You need to make sure that one is connected well .
     
  6. Nov 13, 2011 at 7:29 AM
    #6
    HuckleSmothered

    HuckleSmothered [OP] Member

    Joined:
    Nov 9, 2011
    Member:
    #66740
    Messages:
    21
    Gender:
    Male
    Vehicle:
    95 Tacoma Ext Cab
    I can't get the code read since the fuse is out for that (and the cigarette lighter are altogether). Once I replace the fuse, the Check Engine light goes away.

    Wouldn't the body ground be a redundant ground? Since the main, heavy gauge wire goes to the engine block which is the ground as well?
     
  7. Nov 13, 2011 at 7:59 AM
    #7
    TMW

    TMW Well-Known Member

    Joined:
    Apr 21, 2011
    Member:
    #55300
    Messages:
    317
    Gender:
    Male
    First Name:
    Tom
    Bakersfield, CA
    Vehicle:
    04 Tacoma 4x4 SR5
    Light bar and bumper guard, 3/16 steel skid plates for engine, tranny and transfer box, OME 881 springs with 5100 shocks at mid clip. AAL in rear. Positraction rear diff.
    The heavy wire goes to the engine and is ground for the starter. The smaller wire attaches to the body and is a shield ground. While the engine has many connections to the body they are not necessarily a tight connection. The small wire ensures a good connection. There may be other ground straps attached between the engine and body as well but the one at the battery is the more important one.
     
  8. Nov 14, 2011 at 1:46 PM
    #8
    HuckleSmothered

    HuckleSmothered [OP] Member

    Joined:
    Nov 9, 2011
    Member:
    #66740
    Messages:
    21
    Gender:
    Male
    Vehicle:
    95 Tacoma Ext Cab
    The latest Check Engine light was for this issue. Once I made a makeshift riser for my battery so that it would tighten down securely, I refastened the shield ground (the one that is about 3 inches from the negative terminal to the body) and the Check Engine light went off.

    Thank you.
     
  9. Apr 3, 2012 at 6:40 AM
    #9
    Shadetree

    Shadetree Well-Known Member

    Joined:
    Dec 22, 2010
    Member:
    #48053
    Messages:
    602
    Gender:
    Male
    First Name:
    BiLL
    Bozeman, Montana
    Vehicle:
    2011 Access Cab 4x2
    Locking Tailgate & Gas Cap and extra bed D-rings
    The ground connections on the battery, frame and engine are just as important as the power connections. I would clean them to bear metal. Proper wire size is also important to prevent excessive voltage loss or overheating.
     
  10. Apr 3, 2012 at 6:59 AM
    #10
    Janster

    Janster Old & Forgetful

    Joined:
    Mar 25, 2007
    Member:
    #1138
    Messages:
    14,256
    Gender:
    Female
    First Name:
    Jandy
    Lancaster, PA
    Vehicle:
    2016 GMC Canyon SLT w/ LineX and....
    Yeah...actually, if that 'ground' wire comes off.....or is disconnected, you won't be able to start the truck. Been there done that on a previous vehicle....
     
  11. Apr 3, 2012 at 9:35 PM
    #11
    tan4x4

    tan4x4 Well-Known Member

    Joined:
    Nov 30, 2011
    Member:
    #67982
    Messages:
    3,151
    Gender:
    Male
    First Name:
    Rick
    Folsom, CA
    Vehicle:
    99 Tacoma EC 4x4 2.7L Auto
    Bilsteins, OME 881's, 3-leaf AAL, Detroit TruTrac, 31" tires, Michelin LTX AT2, Tranny skidplate, TC skidplate, CBI rear bumper, TG sliders, UltraGauge, PowerTank, Reverse Camera, CB
    The previous owner was an idiot (as far as the truck is concerned).

    You need to get the right size battery in there, and make sure
    the hold-down works properly. If that is missing, get one
    from a wrecker. Then connect that ground wire.
    Missing grounds can cause all kinds of problems.
     
  12. Apr 3, 2012 at 9:39 PM
    #12
    babytruck

    babytruck Babytruck, babytruck...I've got a babytruck :)

    Joined:
    May 17, 2011
    Member:
    #56797
    Messages:
    8,997
    Gender:
    Female
    NorCal
    Vehicle:
    2010 Barcelona AC 4x4 4.0 6spd
    O hai guise?

    I think the OP resolved this back in November of 2011. Not sure if he will see your suggestions...But still nice of you to help out. :)
     
  13. Apr 3, 2012 at 9:40 PM
    #13
    TrdSurgie

    TrdSurgie revised

    Joined:
    Feb 19, 2012
    Member:
    #73132
    Messages:
    3,527
    Gender:
    Male
    SoCal
    Replace the ground wire and re ground it. Bolt the battery down.

    Edit. Damn......
     
To Top