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DRL power usage?

Discussion in 'Gen 3 Prius Main Forum' started by LDB, Sep 5, 2015.

  1. LDB

    LDB Member

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    Obviously there's no free lunch and no free light. How much power do the DRL's use? I see in the manual there's a DRL off setting on the headlight switch. I've also seen a thread about making the DRL stay on all the time. I liked the look of that when I saw the thread but didn't have a Prius mindset yet that every amp is golden. So now that I'm thinking gain every bit of power from anywhere it's available I'm curious how much power the DRL use and if I should trade power for the cool DRL all the time or not.
     
    #1 LDB, Sep 5, 2015
  2. lester williams

    lester williams Member

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    As far as I know, the DRLs are LED and will use little power. I think they stay on in daylight when the light switch is set in ''auto''. That is where I keep mine on all our vehicles. Someone will come along with a more accurate reply.....I don't think those two small LED running lights will draw enough to make any discernible difference
     
    #2 lester williams, Sep 5, 2015
  3. fuzzy1

    fuzzy1 Senior Member

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    You're in luck, I happen to have a replacement unit for a DRL that ate a rock.

    They are 7.2 watts each, at 12V, according to markings on the housing. When I measured it on a battery in the house, it was indeed drawing 600 mA. I didn't play with it enough to determine if it is really constant current, or if the draw increases when the supply rises to 13-14 V.
     
    #3 fuzzy1, Sep 5, 2015
  4. Mendel Leisk

    Mendel Leisk Senior Member

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    There is a reason for Daytime Running Lights, let's not lose track of that, lol.
     
    #4 Mendel Leisk, Sep 5, 2015
    BruceInOKC likes this.
  5. xliderider

    xliderider Senior Member

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    Not all trim levels have the Auto switch position on the light stalk.

    The difference in mpg with DRLs on vs off is pretty negligible, similar to wheel covers on vs off with the oem alloy wheels.
     
    #5 xliderider, Sep 5, 2015
  6. CR94

    CR94 Senior Member

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    If they're really only about 15 watts total, that would be only a small fraction of the 1% or 1 mpg often vaguely claimed for the wheel covers.
     
    #6 CR94, Sep 5, 2015
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