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Problem with 2012 Toyota Prius headlights.

Discussion in 'Newbie Forum' started by Lntnln, Apr 3, 2017.

  1. Lntnln

    Lntnln Junior Member

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    I am having a problem with the headlights or perhaps the lighting system with a 2012 Toyota Prius. I am not much of a car person but will describe the problem as best as I can.

    Basically, the only thing working on the front lights of the vehicle for now are my turn signals, marker lights, high beam and the small left and right lights to the side of the headlight.

    So the daytime running light and headlight are not working thus when I drive at night, the only light that comes on in the front is the marker, so I have to switch to high beam to have some light.

    A mechanic friend tested the fuse for the lights and none of them is blown, also the bulbs are not burnt out, the filaments are intact.

    The next step is probably visit a Toyota repair shop or the dealership but I am wondering if anyone on this thread may have a suggestion etc.

    Thanks in advance for any help.
     
  2. DonDNH

    DonDNH Senior Member

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    Could be the headlight switch or relays causing the problem.
     
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  3. jerrymildred

    jerrymildred Senior Member

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    Both low beams burned out, maybe?
     
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  4. Lntnln

    Lntnln Junior Member

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    Both cannot or should not burn out at the same time I have been told. Also, a visual check of the bulbs showed the filament is intact and not burned. Plus, I think something is funky somewhere since the low beam/high beam should be using the same source/bulb. High beam comes on but the regular low beam does not come on.
     
  5. Lntnln

    Lntnln Junior Member

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    Will look into the switch but that may possibly mean two switches going bad at the same time? For the relay, there was a spare plus that of the wiper blades which is same as the one controlling lights so we swapped them out, but it didn't work
     
  6. jerrymildred

    jerrymildred Senior Member

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    Gen 2 uses the same bulb. Not so with the Gen 3. The low beam is the cloudy looking one and the high beam is the clear one. So I don't think you can see the low beam filament when it's in place. But there's no reason one could not have burned out and not been noticed till the second one burned out. Or it could be something else.

    If it turns out to be the bulbs, the low beam is an H11 and the high beam is an HB3. Here's a link to the procedure if you wind up needing it. Toyota Prius Headlight Bulbs Replacement Guide - 2010 To 2015 Model Years - Picture Illustrated Automotive Maintenance DIY Instructions
     
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  7. xliderider

    xliderider Senior Member

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    Sounds like you're confusing fuses and relays. There are no spare relays, the relays are larger, typically square plastic "boxes".

    Did your friend physically remove the lowbeam H11 bulbs and check them, either with a multimeter or by connecting them to the battery/jump terminal and ground to see them actually light up?
     
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  8. Lntnln

    Lntnln Junior Member

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    Yes, that is what he did
    Thanks for the link.
     
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  9. Lntnln

    Lntnln Junior Member

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    It's possible, I am bad with this car thing, I am referring to spare fuses and something that looked like a 3pin connector. One of them even controls the wiper. We did a visual check when he pulled them out. Will ask him to test the bulb as suggested.
     
  10. Lntnln

    Lntnln Junior Member

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    Yes both.
     
  11. bobzchemist

    bobzchemist Active Member

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    To do diagnostics on anything (not just cars) it's always helpful to test with a "known good x".

    For example, start with a brand new H11 bulb. Test it with a 12v power supply. If it lights up, you know both the bulb and the power supply are working (known to be good). Remove the H11 bulb from your Prius, and replace it with the new one. Does it light up? If it doesn't, somehow you're not getting power to the bulb. You know this for sure because you just tested the bulb. You can test the bulb sockets the same way, and the wiring, and so forth.

    Next, though, I'd test the old bulb on the 12v power supply. Does it light up? If it does, then you have a break in your circuit somewhere. But if it doesn't, you may have a power surge problem along with a short circuit.

    Multimeters help a lot for this. They're available cheaply at Harbor Freight.
     
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  12. Lntnln

    Lntnln Junior Member

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    Thanks!