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  1. #1
    Jr. Mechanic
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    Default Low Voltage, Dimming lights.

    Alright, i got a 03 1500hd, 6.0. When i accelerate, the volt meter drops to about 9, my lights will be almost off, but when my truck shifts to the next gear the volts come back up and the lights get brighter again. I had the alternator checked but nobody can seem to say whats wrong with it. any help is awesome.
    2003 K1500HD-Straight Pipe, Drop -In K&N Filter, 3" Lift Soon, H2 Rims
    1993 C1500 ECSB- Open Headers, Performance Shift Kit

  2. #2
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    murdog94's Avatar
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    Default

    something i would try is have the battery load tested, and check the chassis grounds to be sure they arent loose.
    Mike

    Currently

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  3. #3

    Default

    Quote Originally Posted by murdog94 View Post
    something i would try is have the battery load tested, and check the chassis grounds to be sure they arent loose.
    these were things I was going to suggest. Also maybe (just a guess), the regulator on the alternator could be going bad. most new ones are internal so a new alternator would be needed. but do the original suggestion first as it is free.
    David
    2004 Silverado 2500 Crew Cab 4x4, AMSOIL EA air filter, Granatelli MAF sensor, Throttle body spacer, Magnaflow exhaust (true dual to 2 in 1 out muffler), 6" ProComp lift (add a leaf and 5" superlift rear block), Bilstein shocks, 35's (Cooper Disoverer ST) and 4.10 gears, Rhino Liner, EGRUSA fender Flares and widow visors, extended stainless steel brake lines, firestone airbags w/onboard air compressor, Pioneer Avic X940BT navigation, Accel backup camera.
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  4. #4

    Default

    actually from what I was told most of the new ones are regulated by the computer (could be wrong, but that came from a GM mechanic). And barring grounding/other electrical issues, I could see that as being likely in your scenario.

    I think your most likely culprit though is a ground/connection issue.
    1986 Chevy G20 Tow Rig - 5.7 TBI conversion
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  5. #5

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    Quote Originally Posted by dualdj1 View Post
    actually from what I was told most of the new ones are regulated by the computer (could be wrong, but that came from a GM mechanic). And barring grounding/other electrical issues, I could see that as being likely in your scenario.

    I think your most likely culprit though is a ground/connection issue.
    ha, guess I'm a little out of date on new. A day late and a dollar short.

  6. #6

    Default

    No Worries, the only reason I knew was I was digging for alternator compatibility info, and i think it's about mid/late 90's on they use external regulators (through the computer).

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