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Headlights going dim

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Old Mar 27, 2010 | 02:54 PM
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Headlights going dim

Anyone ever have problems with the low beams on your headlights go real dim sometime and then get real bright and go back to being dim again.I checked the wiring to the headlights and it's okay.Any Idea's?
Thanks for your help-Ken
 
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Old Mar 27, 2010 | 07:22 PM
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Find where the lights are grounded and clean the connection. Check for corrosion on the the fuse holder. The only other place I can think of would be in the would be in the light switch itself.
 
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Old Mar 27, 2010 | 08:37 PM
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Is it just the low beam or both high / low that get bright then dim. If all connections are good and clean grounds maybe look at voltage reg.
 
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Old Mar 27, 2010 | 10:16 PM
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You may have a weak ground for your headlights. There are groung wires that go up to the core support above the radiator on each side.
 
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Old Mar 28, 2010 | 08:12 AM
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Just the low beams.I see that wire on top of the radiator.I'm going to clean the wire's this afternoon or tomorrow morning and see if that helps.Thanks guy's for the help.-Ken
Is there any way to check the voltage reg. to see if it's going bad?
 
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Old Mar 28, 2010 | 09:42 AM
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Originally Posted by bigfoot22
Is there any way to check the voltage reg. to see if it's going bad?
Check your running voltage at idle, all ACC off. Then check with the lights on highbeam and heater on high.

Do the same at a high-idle, around 2000 RPM.

You should always have AT LEAST 13.5 or more in those scenarios, ideal would be around 14.2-14.5 volts while running.

Josh
 
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Old Mar 28, 2010 | 10:19 AM
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If it is only happening on low beams, the dimmer switch or connection to it is the most likely culprit. Grounds and everything else is common to the high beams.
 
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Old Mar 28, 2010 | 03:59 PM
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I did'nt think about the dimmer switch.I'll check it all out on monday.Too cold and rainy right now.Thanks again-Ken
 
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