how many headlights should be on?

2007 GMC ACADIA
72,900 MILES
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ANONYMOUS
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Just purchased a 2007 Acadia how many headlights should be on? The high beam and low is on, but there is another set of lights they won't come on
Feb 13, 2013 at 1:40 PM
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WRENCHTECH
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If they are mounted below the headlights, they are fog lights and there will be a separate switch for them to come on with the headlights.
Feb 13, 2013 at 1:55 PM
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SKOJO
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Related question. I just changed by low beam bulbs last night (both of them blew within a week of each other). When I have my high beams on, should the low beams turn off? Right now, when I turn on my high beams, the low beam bulbs turn on too. I never paid attention to this before. Thoughts?
May 3, 2013 at 8:38 AM
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STRAILER
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Yes, they will come on at the same time, it sounds like the alternator voltage regulator is bad allowing too many volts to be generated which blows the headlight bulbs out. To be sure let's test the alternator voltage output by folloing this guide:

https://www.2carpros.com/articles/how-to-check-a-car-alternator

Please run down this guide and report back.


Jul 23, 2022 at 11:38 AM
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