Testing a 12v Illuminated Rocker Switch

Discussion in 'General Electronics Chat' started by Richard Brown, Jan 4, 2016.

  1. Richard Brown

    Thread Starter New Member

    Jan 4, 2016
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    Hello and thanks in advance to anyone offering to help.

    Okay. I've got a 24 volt electric scooter.

    I have an off/on switch that I believe may be faulty. A Google image search indicates to me that this is most likely an "illuminated" switch. (Although I have no idea why it would be)

    The switch has 3 places to connect wires. The wiring schematic indicates that one of these is Ground, and the other two are somehow "hot." The schematic shows 2 Red wires coming FROM the control module, while the Ground wire goes to the "charging circuit."

    I've tested the switch with a multimeter set to test for continuity.
    Per the schematic, from top to bottom #3 (Red) #2 (Red) #1 (Black)
    Test between #1 and #2 (switch off) NO continuity / Test between #1 and #2 (switch on) continuity.
    Test between #1 and #3 (switch off) NO continuity / Test between #1 and #3 (switch on) NO continuity.
    Test between #2 and #3 (switch off) NO continuity / Test between #2 and #3 (switch on) NO continuity.

    My question is this. If #1 is Ground, and the other two are "hot," wouldn't this switch be designed to allow power to flow through the switch when in the "on" position by allowing the current to flow between #2 and #3 with #1 being Ground?

    If so, shouldn't I have continuity between #2 and #3 showing the ability for current to flow through?

    Any help would be greatly appreciated.

    Thank you.
     
  2. dl324

    Distinguished Member

    Mar 30, 2015
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    Do you have a part number for the switch? Or a datasheet?

    If the switch is SPDT, there would never be continuity between #2 and #3; assuming typical break before make functionality.
     
  3. Richard Brown

    Thread Starter New Member

    Jan 4, 2016
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    The side of the switch reads: KCD1
    16A125VAC
    16(4) A 250VAC T85

    1 2 3
     
  4. hp1729

    Well-Known Member

    Nov 23, 2015
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    Any Ohm meter reading between 1 and 3, or 1 and 2? Like a lamp? I am thinking 3 and 2 are the switch and 1 is the ground side of the lamp, black wire.
     
    Last edited: Jan 4, 2016
  5. dl324

    Distinguished Member

    Mar 30, 2015
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    If it's the switch I Googled, there are 18 variants.
    upload_2016-1-4_7-28-26.png
    You might have the 201/N version.
     
  6. Richard Brown

    Thread Starter New Member

    Jan 4, 2016
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    I do know that it's either off or on.

    Between #1 and #2 I get an Ohm reading of 0.0

    Between #2 and #3 all I get is OL
     
  7. Dodgydave

    Distinguished Member

    Jun 22, 2012
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    #3 is the ground connection, its probably got a led in the switch, or neon if its mains.
     
  8. hp1729

    Well-Known Member

    Nov 23, 2015
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    Not likely a neon light at that voltage but maybe an incandescent light that is burned out.
     
  9. hp1729

    Well-Known Member

    Nov 23, 2015
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    What was your first indication of a problem? Was the light just burned out or was the whole thing dead?
     
  10. Richard Brown

    Thread Starter New Member

    Jan 4, 2016
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    Sorry, I was pulled away.

    There was no specific indication of anything wrong. I was attempting to solve a problem in my circuit when I came across the switch. When I tried to test it I got off/on continuity between #1 and #2 but wasn't able to get anything from #3 no matter what combination I tried. I thought this kind of strange as it seemed to me that if it didn't "switch" in any way then what was it's function? spst_illuminated_waterproof_rocker_switch.jpg razor-e300-wiring-diagram-v11.jpg

    According to the schematic, #3 is a power connection, #2 is a power connection, and #1 is a Ground.
    #3 would be on the left, #2 in the center, and #1 on the right.
    Vertically, #3 would be on the top (The same as if the switch were put into the "on" position.)
     
  11. Richard Brown

    Thread Starter New Member

    Jan 4, 2016
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    Well, my wife just threw my switch away accidentally so now I don't even know what switch to ask my local hardware store for in order to replace it.

    Would any of you by chance happen to please know by looking at the schematic what I need to ask them for?

    Thank you.
     
  12. Dodgydave

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    Jun 22, 2012
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  13. Richard Brown

    Thread Starter New Member

    Jan 4, 2016
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    That's going to be the correct one?

    Okay. Well, thank you very much then. I guess we can consider this thread closed and solved! :)
     
  14. hp1729

    Well-Known Member

    Nov 23, 2015
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    Yep, looks like a lighted rocker switch. he ground goes to one side of the light. 24 V light. The other side of the light goes to the switched side of the switch.
     
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