Pin Descriptions for 75 Scout II Ignition Switch

Discussion in 'General IH Tech' started by StanG, Apr 26, 2017.


  1. StanG

    StanG Farmall Cub

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    Hi There! I'm new to the forum and wanted to see if I could get some guidance.

    I have a 75 Scout II 345CID. I am replacing the existing wiring with a kit from Painless. Since I am not using the factory connectors between the main wiring harness and the engine harness, I am having trouble mapping each Pin on the ignition switch. I have the manuals and all the diagrams but wanted to see if someone has a description for each of the 9 pins on the ignition switch.

    Any help would be greatly appreciated!
    Stan
     
  2. MrKenmore

    MrKenmore Y-Block King

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    This is my 1978 ignition switch diagram. You should have something similar if you have the shop manual. It's pretty simple. Not too many terminals to deal with.[​IMG]

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  3. MrKenmore

    MrKenmore Y-Block King

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    And plan on getting Packard 56 electrical connectors to do this properly. You should reuse your old plastic connector housing and run your new Painless wires to it with new terminals. One of the spades in the switch is a jumbo size so be mindful of that. Remember it's a GM switch so there should lots out there to research.

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    Last edited: Apr 27, 2017
  4. Patrick Morris

    Patrick Morris Lives in an IH Dealership

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    I was going to mention this earlier as I read the first post. I believe these Borg Warner CS83(?) switches were used in Camaros, etc. etc. for many model years. Should be a lot of info available online.
     
  5. StanG

    StanG Farmall Cub

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    Thanks guys! I have not seen that particular shop manual page! Very helpful. Also helpful hints about reusing the plastic connector housings!
     
  6. MrKenmore

    MrKenmore Y-Block King

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    I'll take a swing at this as I am bored on my railroad commute home:

    I3 - Field wire to alternator
    I1 - Ignition coil positive
    S - Starter
    A - Switched 12V main feed to fuse panel.
    B1 - Constant 12V (stock configuration should be from the back of the fuse panel which then goes to the ammeter)
    G2 - Brake system warning light


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  7. MrKenmore

    MrKenmore Y-Block King

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    You're quite welcome! I'm not sure how the Painless kit works or if there are other wires that they need to get hooked up at the ignition switch but the position legend (what's on/off in different key positions) will help.

    Remember for your alternator field wire, you need a warning light or a resistor. Check the Painless kit has incorporated this provision.

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  8. StanG

    StanG Farmall Cub

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    Thanks for the mapping! Also, I checked the Painless instructions and they do accommodate for the alternator field wire.
     
  9. MrKenmore

    MrKenmore Y-Block King

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    You're welcome. Make sure you double check my work. I am pretty confident though. :clap:

    I'm curious what Painless does off the ignition switch as stock configuration is fusible link wires. Three of the outputs I believe.
     
  10. StanG

    StanG Farmall Cub

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    IMG_0502.JPG Here is a high level electrical layout for the alternator, ignition switch, and starter....
     
  11. MrKenmore

    MrKenmore Y-Block King

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    OK. You'll be in good shape. Only four wires to connect!! I do wonder why they have the alternator voltage sense wire (#2 as they indicate) jump back to the big post on the alternator. This really defeats the function of the voltage sensing. It should go to your primary distribution point where the alternator senses the needs and requirements of the system. When it's hooked onto itself, it'll always say "I've got full voltage! No need to put out any more." MAD Electrical does an amazing job describing this (http://www.madelectrical.com/electricaltech/remotevoltagesensing.shtml). The other electrical tech articles are excellent as well.

    Which Painless kit did you get? 90548?
     

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