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Has anyone measured voltage drop in headlight wiring on their 2nd gen?

Discussion in 'Lighting' started by iroc409, Aug 28, 2011.

  1. Aug 28, 2011 at 10:24 AM
    #1
    iroc409

    iroc409 [OP] Well-Known Member

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    I am just curious if anyone has ever done this. I know a few people have created relay harnesses for the headlights, but can't remember if anyone checked the voltage drop first.

    I'm guessing there is some. There's a lot of stuff on the circuits, and I'm guessing (just from memory) the wiring is only 20-ga.
     
  2. Aug 28, 2011 at 10:42 AM
    #2
    cummins6speed

    cummins6speed Well-Known Member

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    The headlights are already on a relay. I doubt there is really any voltage drop on the wiring
     
  3. Aug 28, 2011 at 12:17 PM
    #3
    iroc409

    iroc409 [OP] Well-Known Member

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    Yeah, I would think relays would reduce the drop considerably. However, there's a few other things running off the headlight circuit, like the fog relay, in-cab indicators, etc (and the tiny wiring). They're running between the headlight relay and the bulb.

    I was just curious, as I've thought about building a harness but don't really want to go to the expense. I'm upgrading my cheap aux fuse block and adding new auxiliary lights (had some on previously but wasn't happy with them), so I'm ordering parts.
     
  4. Sep 12, 2011 at 3:08 AM
    #4
    iroc409

    iroc409 [OP] Well-Known Member

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    As an update, I was able to measure voltage drop on my headlights with the engine off and headlights on.

    Looks like about .45v drop on the driver bulb, and .75-.8v drop on the passenger bulb. More than I expected.
     
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