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  1. #1
    FEP Member Sask84gt's Avatar
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    Default Need help identifying a cut wire.

    Anyone know what this cut from and what its purpose is? It's off the main harness on passenger side. Car is a 84 gt.

    Thanks
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  2. #2
    FEP Senior Member OX1's Avatar
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    Quote Originally Posted by Sask84gt View Post
    Anyone know what this cut from and what its purpose is? It's off the main harness on passenger side. Car is a 84 gt.
    Typically that large yellow wire is the feed for the ign switch and ultimately everything that gets turned on by the ign switch

    See 84 wiring diag here.

    http://vb.foureyedpride.com/showthre...79-1986-in-PDF
    86 Capri, 5.0, 5Spd, A9L QH/BE, 47 lb Inj PMAS 3" MAF, Single T44 Turbo, Front Mount IC, TW170,
    Stock Cam, Explr Intake/TB, 1.7 Rockers, CF dual friction clutch, 3" DP, 2.5" full Exh, 3.27, 11.932 @ 115.78
    84 LTD, 331-10:1, TW170/Exprl Intake, 47 lbs inj/80 mm LMAF, Full Duals, Quarterhorse, Vortech 7PSI, Lentech AOD, 5 lug Mk VII brakes/rear, Eibach Sway bars, Cobra HB (dads ride, but I fix it )

  3. #3
    FEP Member Sask84gt's Avatar
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    Quote Originally Posted by OX1 View Post
    Typically that large yellow wire is the feed for the ign switch and ultimately everything that gets turned on by the ign switch

    See 84 wiring diag here.

    http://vb.foureyedpride.com/showthre...79-1986-in-PDF
    Ok, so why would it be cut? Seems pretty important to me lol. Note, it was like that when I bought it and also had the motor removed.
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  4. #4
    FEP Member Sask84gt's Avatar
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    Looks like it was cut from here.
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  5. #5

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    Just trying to bump your thread and I'm tending to side with those saying it's typical of the large Yellow wire that goes from the ignition switch to the starter relay (aka solenoid). Supposedly it provides power to the inside of the car from its connection at the solenoid and I believe in some cases it's also connected to/with a Fusible Link. Quite a few guys say this Yellow wire enters the passenger compartment on the passenger side under the dash and is connected to the rear window defrost. Maybe some others will chime in to verify . . .

    If you take a look at the first minute of this Yootube vid (a empty Fox engine bay) I'm pretty sure that's your wire attached to the solenoid

    https://www.youtube.com/watch?v=HkMgDLt8DBw
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  6. #6
    FEP Senior Member OX1's Avatar
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    Quote Originally Posted by Sask84gt View Post
    Ok, so why would it be cut? Seems pretty important to me lol. Note, it was like that when I bought it and also had the motor removed.
    If you still have power to the ign switch and rear defroster (as mentioned, that yellow wire usually powers feed to
    rear defrost relay) then someone ran a seperate non-factory wire instead of the cut one.

    Does ign and read defrost work?
    86 Capri, 5.0, 5Spd, A9L QH/BE, 47 lb Inj PMAS 3" MAF, Single T44 Turbo, Front Mount IC, TW170,
    Stock Cam, Explr Intake/TB, 1.7 Rockers, CF dual friction clutch, 3" DP, 2.5" full Exh, 3.27, 11.932 @ 115.78
    84 LTD, 331-10:1, TW170/Exprl Intake, 47 lbs inj/80 mm LMAF, Full Duals, Quarterhorse, Vortech 7PSI, Lentech AOD, 5 lug Mk VII brakes/rear, Eibach Sway bars, Cobra HB (dads ride, but I fix it )

  7. #7
    FEP Member Sask84gt's Avatar
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    Quote Originally Posted by OX1 View Post
    If you still have power to the ign switch and rear defroster (as mentioned, that yellow wire usually powers feed to
    rear defrost relay) then someone ran a seperate non-factory wire instead of the cut one.

    Does ign and read defrost work?
    Not sure, motor was out of car. I've been in contact with previous owner and he said it was running and driving before he took motor out due to a leak of some sort. He thinks it's a accessory wire of some sort.
    Mustangs
    84.5 Gt T-top
    85 Gt

  8. #8
    FEP Senior Member OX1's Avatar
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    Quote Originally Posted by Sask84gt View Post
    Not sure, motor was out of car. I've been in contact with previous owner and he said it was running and driving before he took motor out due to a leak of some sort. He thinks it's a accessory wire of some sort.
    You don't need motor in to see if that is main ign wire. Hook chassis ground up to neg batt and then hook pos side of batt up to yellow wire.
    Try ign switch. If it works, then disconnect that wire, ign will probably not work.
    86 Capri, 5.0, 5Spd, A9L QH/BE, 47 lb Inj PMAS 3" MAF, Single T44 Turbo, Front Mount IC, TW170,
    Stock Cam, Explr Intake/TB, 1.7 Rockers, CF dual friction clutch, 3" DP, 2.5" full Exh, 3.27, 11.932 @ 115.78
    84 LTD, 331-10:1, TW170/Exprl Intake, 47 lbs inj/80 mm LMAF, Full Duals, Quarterhorse, Vortech 7PSI, Lentech AOD, 5 lug Mk VII brakes/rear, Eibach Sway bars, Cobra HB (dads ride, but I fix it )

  9. #9

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    On my 85, that big yellow wire is for the rear defrost.
    1985 GT, Sunroof, 5 Lug, Rear Discs, 01 Graphite Bullets, 88 forged piston shortblock, 2.02/1.60 Alum heads, Weiand Stealth, Holley C950 TBI, BBK Long tubes

  10. #10
    FEP Member Sask84gt's Avatar
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    Quote Originally Posted by droopie85gt View Post
    On my 85, that big yellow wire is for the rear defrost.
    Ya that's what previous owner said it probably was.
    Mustangs
    84.5 Gt T-top
    85 Gt

  11. #11
    FEP Member Sask84gt's Avatar
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    Update
    Hooked up battery and had power to inside of car and also starter so that yellow wire must be rear defrost.
    Mustangs
    84.5 Gt T-top
    85 Gt

  12. #12

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    As others have said , yellow is rear defrost. The two light tan wires are fog light power. Tan wire is from the passenger marker light and runs to the fog light switch as one power for a double power relay. Black wire is the ground for the fog light switches light.
    84 20th Anny 2.3Turbo #1978
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  13. #13
    FEP Member Sask84gt's Avatar
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    Quote Originally Posted by GT350R View Post
    As others have said , yellow is rear defrost. The two light tan wires are fog light power. Tan wire is from the passenger marker light and runs to the fog light switch as one power for a double power relay. Black wire is the ground for the fog light switches light.
    Thanks for the info, I'm going to attempt to solder them all back together.
    Mustangs
    84.5 Gt T-top
    85 Gt

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