Question about 1993 GMC Sierra K1500

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12 volt alternator putting 24 to 48 vols

I have a boat alternator that show 24 to 48 volts at output but is 12 v alternator tried 2 new ones same thing???

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  • michel_lapoi Jul 02, 2009

    I am positive of my tester further more if I check at the battery i get a flat 12v just on the alternator output i have 24v also the exciter wire should it have power after engine start

  • michel_lapoi Jul 02, 2009

    I am positive of my tester further more if I check at the battery i get a flat 12v just on the alternator output i have 24v also the exciter wire should it have power after engine start

  • Marvin
    Marvin May 11, 2010

    are you sure your meter is set right and are u sure it is working? if the volts where that high it would blow out everything in the boat.



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Try another multi-meter or change the settings... 12V alternators cannot produce 48V.

Posted on Jul 02, 2009


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