Voltage pulsates on 71 Ford truck

Discussion in 'Other Automotive Tech & Talk' started by Old Guy, Oct 30, 2007.

  1. Old Guy

    Old Guy Member

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    Have replaced regulator, alternator, etc. Turn on headlights and they pulse bright, dim. Also show's on ohm meter, on any hot wire, any idea's?
     
    Old Guy, Oct 30, 2007
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  2. dkstuck

    dkstuck Member

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    Check your ground real good. Probably replace headlight switch,

    When you put the meter on, was it at headlights? With engine running an no lights turned on, check batt voltage. Also, do headlights dim without engine running?
     
    dkstuck, Oct 30, 2007
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  3. newtoford

    newtoford Member

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    do they still pulse at higher rpm's or just at idle? what about when the car is off?
     
    newtoford, Oct 30, 2007
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  4. CornedBeef4.6L

    CornedBeef4.6L no longer here

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    It may be in turn signal assembly do yourself a favor and unplug the flash as well........

    Past that i would also look for grounds!!!!
     
    CornedBeef4.6L, Oct 30, 2007
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  5. Derek 5oComet

    Derek 5oComet Tire burner

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    I have had headlight and dimmer switches cause that too.
     
    Derek 5oComet, Oct 30, 2007
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  6. Andysutt

    Andysutt '72 Comet GT

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    I had a brand new alternator do that also before on that GMC of mine.

    It went out, put a new one on... it pulsed for a bit until it bit the dust before i could remove and take it back (less than a week)

    Matter of fact, I changed it out at your house with Junior.
     
    Andysutt, Nov 1, 2007
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