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Illumination wire?

Discussion in 'Lighting Discussion' started by SurrealOne, Jan 20, 2013.

  1. Enkeiavalanche

    Enkeiavalanche Rockstar 4 Years ROTM Winner 5000 Posts

    Gotta say those are some Nice looking Switches.....
  2. zigger215

    zigger215 Member 2 Years 500 Posts

    It's not a "reverse ground". That doesn't even exist. It's a negative trigger meaning the power is constant but the impedance to ground fluctuates which causing the dimming in the lights. The symbol you're lookin for is "-". Just like our parking lights.

    Having worked professionally in the mobile installation industry and now as an IBEW wireman who has done tons of PLC installations, I can say they are nothing like cars....
  3. SurrealOne

    SurrealOne Former Member ROTM Winner 1000 Posts

    Pardon my fumbled terminology.

    Pikey, I'll let you know when I test -- should be this weekend, weather permitting.
  4. Pikey

    Pikey Moderator Staff Member 2 Years ROTM Winner 1000 Posts

    I looked at the diagram again and it does not have any indication. I also looked at the parking light circuit diagram. It did not indicate a negative trigger either. Maybe the publisher "forgot" that part.
  5. zigger215

    zigger215 Member 2 Years 500 Posts

    Pikey I can tell you from years and years of experience that these trucks have many "negative trigger" circuits, park lights being one of them. Apply 12v to the grey/black wire on the switch and watch the free fireworks show...
  6. zigger215

    zigger215 Member 2 Years 500 Posts

    There you go, that's what a negative trigger looks like on direct wire. This is a complete schematic (way more in depth than a Haynes book) for a 2004 silverado.
  7. Pikey

    Pikey Moderator Staff Member 2 Years ROTM Winner 1000 Posts

    Oh, I am not doubting you in any way. I am just stating that my manual does not indicate the (-). I would always use a multimeter to figure out what was going on before i attempted any mods/repairs on an electrical system. I have seen way too many inconsistencies in wiring diagrams to trust anything 100%
  8. zigger215

    zigger215 Member 2 Years 500 Posts

    That's also pretty dang true. Always double check with a meter, I second that. I will say, GM has been awesome with their consistency on our trucks, I always loved working on our trucks when they came in the shop. I always knew what I was getting good or bad
  9. SurrealOne

    SurrealOne Former Member ROTM Winner 1000 Posts

    I decided to go for a connection at the dimmer switch in the cab just because it's a place I knew I could easily probe. After removing my sound deadening material, cutting new material to fit (for when I finish), and probing/testing with a multi-meter, here's the verdict:

    The wire (at the dimer switch) is brown with a white stripe and is NOT a negative trigger.
    Last edited: Jan 27, 2013
  10. Scooter

    Scooter Rockstar 100 Posts

    Hey Zigger what app is that on your phone?

    Hey surreal I always love your work, I know you said 85 bucks for just the four switches but what did the whole setup run you. And would you be willing to do another similiar?

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