Light switch puzzle. Fuse? Relay? Wiring?

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by sahuaprius, Mar 30, 2023.

  1. sahuaprius

    sahuaprius New Member

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    Hey everyone. The standard headlights and orange parking lights are acting up on my 2008 Toyota Prius. The brights work just fine. Issues are in the front only. Here's what happens when I mess with the light switch (stick).

    Light switch first position (off): fine
    Light switch second position (parking lights): front parking lights don't come on
    Light switch third position: headlights don't come on
    Light switch brights position: brights come on
    Hazards: parking lights come on just fine

    When I flip the light switch on to the third position and turn off the car, the car beeps to alert me that my lights are on.

    Ideas? Would very much like to drive with standard headlights again.
     
    #1 sahuaprius, Mar 30, 2023
  2. bisco

    bisco cookie crumbler

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    bad switch?
     
    #2 bisco, Mar 30, 2023
  3. Eddie25

    Eddie25 Active Member

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    Probably a fuse, check any of them associated with headlights.
     
    #3 Eddie25, Mar 30, 2023
  4. ChapmanF

    ChapmanF Senior Member

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    #4 ChapmanF, Mar 30, 2023
  5. xliderider

    xliderider Senior Member

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    #5 xliderider, Mar 30, 2023
  6. sahuaprius

    sahuaprius New Member

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    This seems like the most likely answer but it is difficult to say because I'm not sure how to test the switch itself...

    Just checked. Fuses are fine.
     
    #6 sahuaprius, Mar 30, 2023
    Last edited by a moderator: Mar 30, 2023
  7. Eddie25

    Eddie25 Active Member

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    It does seem like the switch. Here's the wiring diagram, it's page 288. Looks like Pin 18 (yellow) is power and Pin 12 (green) is ground, from what I can tell you should have continuity in Tail and Head position, that's probably the first thing I'd check, but I'm just thinking out loud, you'll have to verify this yourself.
     

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    #7 Eddie25, Mar 30, 2023
  8. mr_guy_mann

    mr_guy_mann Senior Member

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    I would say this is a silly question, but I have had customers do this. Have you checked that the bulbs in question are actually good? The low beam filaments can be burned out but the high beams (part of the same 9003 bulb) can work fine.

    The front parking lights are separate from the front turn signal bulbs.

    You may have other problems, but since voltage testing should start at the bulb sockets, why not confirm that the bulbs are capable of illuminating?

    Posted via the PriusChat mobile app.
     
    #8 mr_guy_mann, Mar 31, 2023
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