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Low beams do not work

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by roman6236, Dec 16, 2010.

  1. roman6236

    roman6236 New Member

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    Driver side bulb does not work on low beam but does work on high. Replaced the halogen bulb but problem persists. Any advice? The dealership checked the fuses which were fine. No further diagnostics done as I already spent more time at the dealership than anticipated. Hoping I can find a solution here. Thanks in advance.
     
    #1 roman6236, Dec 16, 2010
  2. Patrick Wong

    Patrick Wong DIY Enthusiast

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    Use a voltmeter to determine whether you can measure 12V at the bulb socket when the headlight switch is on. If yes, then the problem is with the bulb. If no, then the problem is with the socket, wiring harness or fuse.
     
    #2 Patrick Wong, Dec 16, 2010
  3. roman6236

    roman6236 New Member

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    Thanks. I'm amazed that something so simple to diagnose was missed by Caldwell Toyota in NJ. They told me they would have to remove the bumper to get at the assembly charging me approximately $150 to diagnose and repair. Thank goodness I walked away. Won't be going there any more. Could a blown fuse also cause this?
     
    #3 roman6236, Dec 17, 2010
  4. Troyroy

    Troyroy Member

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    Had this same problem with Daughters Hyundia...it's the metal contacts built into the headlight assembly...not the bulb. You or dealer has to bend the contacts out to make better contact with the bulb.
     
    #4 Troyroy, Dec 17, 2010
  5. Patrick Wong

    Patrick Wong DIY Enthusiast

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    Although I am currently traveling and don't have access to the electrical wiring diagram, I recall that each headlight bulb filament has its own fuse protection. Therefore it would be appropriate to find the correct fuse, remove it, and measure its resistance (should be ~0 ohms.)

    While you are there, you could also turn the headlight switch on, and measure for the presence of 12VDC at one of the fuse terminals, while the fuse is removed. If you don't find voltage then you know your problem is upstream from the fuse.
     
    #5 Patrick Wong, Dec 18, 2010
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