battery light flickering

2005 SCION XB
72,000 MILES
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WILLIAM.SNIDER
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when im driving my car and i give it gas around 3k rpms the battery light will flicker and it will***** and try to die, the battery and alternator was tested at autozone and they said it was fine and that was at numerous stores. i have no idea where to even look to see what the problem is.
Oct 17, 2011 at 3:47 AM
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RIVERMIKERAT
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Use a multimeter to check the alternator output. It should be between 13.8 and 14.2 volts. It could be the rectifier diode in the alternator getting ready to go bad.
Oct 17, 2011 at 4:55 AM
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RASMATAZ
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Could be the computer controlled of the alternator's fiel generation circuit

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Oct 17, 2011 at 4:59 AM
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WILLIAM.SNIDER
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It's a brand new alternator just put it on 2 days ago myself and it's pushing 14.1, I also found out that the battery light flickers but the car doesn't try to do if the head lights are off but if they are on or the fan or radio is on high it will***** and try to die
Oct 17, 2011 at 5:40 AM
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RIVERMIKERAT
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Check the grounds for those circuits.
Oct 17, 2011 at 6:23 AM
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