HIgh beams stuck/won't turn off

Discussion in 'Gen 2 Prius Care, Maintenance and Troubleshooting' started by richardchaven, Jun 6, 2010.

  1. richardchaven

    richardchaven Junior Member

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    Anytime I turn the headlights on, the high beams go on too; I cannot switch off the high beams unless I turn off the headlights entirely (I have been driving with the low beams on during the day for the 5 years I have had the car)

    I can find no reason for this; I'm inspecting the fuses (with little expectation). The only thing I can think of is the control switch or wiring.

    Update: I have standard headlamps, not hid.

    Update: I am in California (daylight use of headlamps is voluntary)

    Any ideas?
     
    #1 richardchaven, Jun 6, 2010
  2. Patrick Wong

    Patrick Wong DIY Enthusiast

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    Does your car have halogen headlights or HID headlights? (If you don't know, HID headlights are accompanied with foglights.)
     
    #2 Patrick Wong, Jun 6, 2010
  3. BAllanJ

    BAllanJ Active Member

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    You don't say what country you're in... if it's a car first sold in Canada, you'll have daytime running lights which can't be turned off.
     
    #3 BAllanJ, Jun 6, 2010
  4. Patrick Wong

    Patrick Wong DIY Enthusiast

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    The obvious suspects would be the headlight relay or the dimmer switch being stuck in the high beam position. Does the blue headlight icon stay on all the time, or will it go on and off as you operate the headlight dimmer switch?

    If you have a multimeter available, you can test the headlight relay by removing it from its socket in the main relay/fuse box, figuring out which terminals are the relay coil terminals by using the ohmmeter function (the resistance across the coil terminals will be around 100 ohms or so), then applying 12VDC to the relay coil terminals to see whether this causes the switched terminals to switch. (The relay controls a single-pole double-throw switch function.)
     
    #4 Patrick Wong, Jun 7, 2010
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