Question about 2004 Ford F150

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2001 Ford F150 battery light comes on at running speeds, but will go off at idel. Battery hand shows charging. Battery and alternator test good.

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  • jreed25 Nov 17, 2009

    Autozone hooked it up and test the battery and alternator. I don't know if that checks the diode

  • Steve S
    Steve S May 11, 2010

    The test for the Alternator, did they check for an overcharge condition at higher RPMs ? The battery light will come on with both an over and under charge condition.

  • timj02 May 11, 2010

    did they run a diode test on the alternator and you should check the voltage regulator aswell



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Verify the belt tension-er is staying tight and not floppy around at higher RPMS,or the belt is not slipping ,have the alternator checked at higher RPMS not at an idle.the last is make sure the single wire little wire connector is tight

Posted on Nov 22, 2009


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After i changed my alternator on my 2004 ford f150, my check charging system light and battery light comes on. also, my idle is really low now when i come to a stop, sometimes truck dies do to low idle. I...

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Click on the link.
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