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1999 GMC Safari Question: why wont my 1999 gmc safari hold a charge as far as battery alternator goes.

 

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jae mak, Chicago, IL, October 30, 2012, 13:16
 Rookie

i replaced the battery 3 times, replaced the alternator 3 times install a new battery cable (positive)replaced the starter, replaced the the alternator plug and check all the fuse in the fuse boxes under the dash and under the hood and still no charge.

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  • Answer #1

    October 30, 2012, 14:39
     Journeyman

    Are you saying that the battery wont hold a charge or the charging system isnt working? It the battery is losing the charge, (it goes dead) after a day or so then you should be looking for a current draw. Something is staying on and killing the battery. If the charging system isnt working then you need to do some diagnostics to see why the alternator is not doing its job.

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    jae mak, October 30, 2012, 15:00
     Rookie

    the charging system is not working properly even after all the repairs i recently made to it

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    pushrod, October 30, 2012, 15:17
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     Master

    WHAT IS THE VOLTAGE AT THE BATT.WITH THE ENGING RUNNING?

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    jae mak, October 30, 2012, 15:30
     Rookie

    The voltage is between 9 and 10

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    pushrod, October 30, 2012, 15:52
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     Master

    CHECK THE BIG RED WIRE ON THE BACK OF THE ALT. SHOULD BE BATTERY VOLTAGE IS IT? WHEN YOU INSTALLED THE ALT WAS THE BATT. CHARGED UP BEFOR YOU STARTED THE ENG. AND NOT JUST JUMP STARTED? 9-10 VOLTS YOU NEED TO HOOK UP A CHARGER AND GET BATTERY TO FULL CHARGE THEN TRY CHECKING VOLTAGE. THIS IS SUPPOSED TO BE AN EASY ONE. BUT SOMETIMES WELL.

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    jae mak, October 30, 2012, 16:03
     Rookie

    The battery was brand new then I put the 3rd alternator on and still no charge

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  • Answer #2

    October 30, 2012, 16:59
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     Master

    wow, three batteries and three alternators...why didn't you get ANOTHER alternator? anyway, Jae Mak...sounds like you have an issue with the alternator not charging...you have to find out what wire is missing or broken.

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    jae mak, October 30, 2012, 17:09
     Rookie

    Problem I dnt have or know how to use one thar test lights

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    pushrod, October 30, 2012, 20:18
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     Master

    I UNDERSTAND YOU WANTING TO FIX THIS YOURSELF BUT IT IS TIME TO GO SEE A MECHANIC!!
    THE REPAIR SHOULD NOT COST YOU A BUNCH. DON'T BE DISCOURAGED THOUGH YOU WERE ON THE RIGH TRACK.

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  • Answer #3

    November 01, 2012, 15:40
     Master

    Pull the alternator off and have it 'bench tested'. IF it checks out good , leave it off truck. Next , fully slow-charge battery and then buy a multi-meter. Then get a wiring diagram of charging circuit and perform input/output and continuity tests on appropriate wires. Probably failed signal wire to alt. VERIFY FIRST!!! Before putting on more parts.........IF alt. bench tests bad then have the next one you get bench tested before you leave the store with it. Then troubleshoot vehicle before installing alt. Good luck.

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    your.mechanic, November 01, 2012, 15:51
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     Master

    Bench tested by whom? AutoZone? Heck NO! They think anything with "duralast" on it is good to avoid warranty issues and fail anything else that comes in...to sell a "duralast".

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    jae mak, November 01, 2012, 16:03
     Rookie

    I ll try it once the weekend comes along

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    ziptie12, November 02, 2012, 18:46
     Master

    Good luck. I suggest you ask friends for references to a trustworthy shop.

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