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Fog lights/battery drain

Discussion in 'Prius v Accessories and Modifications' started by Thina, Aug 4, 2024 at 6:17 PM.

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  1. Thina

    Thina Junior Member

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    2012 Prius v wagon
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    Three
    So I added LED fog lights (that part isn’t the issue). They work fine. I tapped into the cigarette lighter as I wanted a back-up protection in case I forgot to turn them off.

    however since adding them I’ve had a weird 12v battery issue. I’ve needed the battery jumped once. When starting it, sometimes it starts fine. Other times it almost “forgets” how. While the 12v battery is on the tail end of its life, this was never an issue before.

    what gives? All headlight bulbs are LED.
     
    #1 Thina, Aug 4, 2024 at 6:17 PM
  2. rjparker

    rjparker Tu Humilde Sirviente

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    You could measure the off state parasitic draw. After a couple of minutes it should be 15-30ma assuming you have the hatch closed.

    Try a new 12v. They last a long time but eventually fail and without obvious pattern. I had one fail to Ready the car in a grocery parking lot after driving it for 30 minutes.
     
    #2 rjparker, Aug 4, 2024 at 7:05 PM
    Thina likes this.
  3. BiomedO1

    BiomedO1 Senior Member

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    how was it wired? did you go through a relay or are you pulling all the current through the lighter circuit? If your not going through a relay, then your switch got hot and is partially closed or bridged. Ohm it out; it should be open.
     
    #3 BiomedO1, Aug 4, 2024 at 7:45 PM
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