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Wiring-what Does This Do?

Discussion in 'Early CJ5 and CJ6 Tech' started by colojeepguy, Sep 28, 2019.

  1. Sep 28, 2019
    colojeepguy

    colojeepguy Colorado Springs

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    The connection for my brake light switch has this little....diode? Resistor? between the two sides of the plug. What is it and how do I test it?
    20190928_100400.jpg
     
  2. Sep 28, 2019
    47v6

    47v6 junk wrecker! 2023 Sponsor 2022 Sponsor

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    Might be a diode to stop current flowing from one side to another bypassing the switch? Im not an electrical engineer. I would like others to chime in as I see this type of setup on other non related applications.
     
  3. Sep 28, 2019
    Focker

    Focker That's a terrible idea...What time? Staff Member

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    I'm thinking Chris is right, but I can't confirm.
     
  4. Sep 28, 2019
    Focker

    Focker That's a terrible idea...What time? Staff Member

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    If you're good with a multimeter, you could see if there is current flowing only one direction.
     
    65CJ5 SRD likes this.
  5. Sep 28, 2019
    ITLKSEZ

    ITLKSEZ Hope for the best, prepare for the worst

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    That’s weird. If it’s a diode, any benefit would be negated by the current just flowing through the fuse. After the fuse blows, no current would pass, so no need for a diode.

    Looking forward to an answer on this.
     
  6. Sep 28, 2019
    Glenn

    Glenn Kinda grumpy old man Staff Member

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    Didn't someone mention doing that for flat towing as a method for ease of hooking up brake lights?
     
  7. Sep 28, 2019
    Admiral Cray

    Admiral Cray I want to do this again.. Staff Member

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    It does look like a diode...
     
  8. Sep 28, 2019
    Focker

    Focker That's a terrible idea...What time? Staff Member

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    Yes

    You would use diodes with a permanent trailer harness to avoid backfeeding.
     
    Glenn likes this.
  9. Sep 28, 2019
    mickeykelley

    mickeykelley Well-Known Member

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    Which is on my list for Willie now that I'm flat towing him between Texas and New Mexico and Colorado. Tired of magnetic lightsand want to continue to simplify prep time.
     
  10. Sep 28, 2019
    Glenn

    Glenn Kinda grumpy old man Staff Member

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    That's what I thought.
     
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  11. Sep 28, 2019
    Glenn

    Glenn Kinda grumpy old man Staff Member

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    So then maybe Doug has one on his tail lights too.
     
  12. Sep 28, 2019
    colojeepguy

    colojeepguy Colorado Springs

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    I thought the diode for flat towing went in one of the turn signals? Plus, this Jeep was never towed before I got it and I've always used magnetic lights.
     
  13. Sep 28, 2019
    timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor

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    I don't see an obvious band, so it's unlikely to be a diode. Plus I don't understand how a diode could be useful for towing in this location. If it conducts forward, it defeats the purpose of the switch. If it conducts backwards, that would cause backfeed, not prevent. Might be a varistor or even a capacitor, intended to protect the contacts in the switch from arcing.
     
  14. Sep 28, 2019
    Focker

    Focker That's a terrible idea...What time? Staff Member

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    I don't think we were saying it was used for towing in this particular case. I think we were just trying to remember the discussions earlier about diodes and flat towing?

    I was hoping you would see this thread and shed some light on it.
     
  15. Sep 28, 2019
    Glenn

    Glenn Kinda grumpy old man Staff Member

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    Actually I was trying to wrap my head around how it would work for towing. I guess you didn't realize that I was thinking it must be for towing. After Tim's explanation I see it obviously couldn't work.
     
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  16. Sep 28, 2019
    timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor

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    Looks amateurishly installed, whatever it is. Significant risk of short with all that bare lead exposed. I suspect you can slide the brass contacts out of the plastic shell with a pointy tool like a dental pick or jeweler's screwdriver. Usually the connectors have prongs that snap into the shell, and you can push them back to release the connector. This might reveal how this component is attached to the connector.
     
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  17. Sep 28, 2019
    Glenn

    Glenn Kinda grumpy old man Staff Member

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    Is it logical it could be simply for something to pull from to remove the plug?
     
  18. Sep 28, 2019
    colojeepguy

    colojeepguy Colorado Springs

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    I pulled the wires out of the connector-

    20190928_200432.jpg
    My issue is that this Jeep eats brake light switches, every couple of months. IDK if this thing has anything to do with it, I'm really grasping at straws....
     
  19. Sep 28, 2019
    Glenn

    Glenn Kinda grumpy old man Staff Member

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    I assume you're buying what should be quality switches.
     
  20. Sep 28, 2019
    Howard Eisenhauer

    Howard Eisenhauer Administrator Staff Member

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    Diode for sure, I see no reason for it to be there. Under normal circumstances it would do nothing, under abnormal circumstances... well there are no abnormal circumstances where it would do anything either except put you brake lights on if you connect your battery backwards.

    Note that the plug is not a stock item- that's actually a GM alternator plug, I see no reason to have a diode connected like that on an alt either. :confused:
     
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