Question about 1991 GMC Suburban

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The alternator is putting out no power. Replaced it, am assuming the alternator controller, voltage regulator is defective or inoperative. Where is it located?

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  • jbrock815 Jul 12, 2010

    Not really. Sort of wasted my money with this one.



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The voltage regulator is internal inside the alternator. A couple of things to check would be first if you installed a new alternator check the back of the alternator fof a pin (will look like a bent piece of stiff wire) you must remove this for the alternator to work. It is installed so if you have to clock the alternator to install it on some cars. Also check that the alternator is grounded and that it is getting current if all is fine the new alternator is defective.

Posted on Jul 12, 2010

  • 2 more comments 
  • jbrock815 Jul 12, 2010

    Just checked, there is no wire extend out the back of the alternator.

  • jbrock815 Jul 12, 2010

    Did you get my reply?

  • Ronald Park
    Ronald Park Jul 12, 2010

    If the wire is not sticking out, it would be near the center of the alternator, then that is not the problem check the main heavy red wire should be hot and the frame of the alternator should be grounded if they are correct then the alternator is defective.

  • Ronald Park
    Ronald Park Jul 12, 2010

    Sorry it took awhile I'm not always at the computer but I check it often. That way I can try to keep up with any comments and/or questions. I watch for if you have any more problems I keep on checking.



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