Question about 2004 GMC Yukon

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Headlights dim signifigantly when power windows roll up or down

I have a 2005 GMC yukon. when the power windows are activated, the headlights dim significantly, and they dim really bad when the window is up and you press up or when they are down and you press down. I know that there is no reason to hold the button in either position when the window is in its open or closed position, but if i'm rolling the back windows down i can tell when they are all the way down, because the headlights dim down to about 60% of their max capacity.

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  • Ray Keckeisen May 11, 2010

    you need to have the alternator checked,get back to me and we'll go from there, make sure they test it with a load tester



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This should never happen if everything is normal. It sounds like your alternator is bad also have your battery tested. These parts are about six years old and that is when they usually fail. Check your fan belt is tight and not falling apart.

Posted on May 27, 2009


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