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Old Mar 7, 2009 | 11:01 PM
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electrical problem

alright guys here it is alternator wasn't charging the battery so car died. so i replace the alternator then drive for a day and then battery completely dead so i got my friends optima yellow top. driving to work and home while driving home and dead again i need help with this I'm thinking hopefully its another bad alternator or the cable that goes on the alternator any ideas.
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Old Mar 8, 2009 | 12:15 AM
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yes.........................................try junking it.
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Old Mar 8, 2009 | 12:47 AM
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engrish? post up in the 2nd get archives. they will help you out more.
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Old Mar 8, 2009 | 01:16 AM
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Have you tried to disconnect the negative terminal off the battery while the engine is on? If the engine does stays ON, than your alternator is working but if your engine turns off as soon as you unplug the negative terminal than you Sir have a bad Alternator. As for the battery, i would take that to a local Auto parts store and have them check the CCA and charging defects. Good luck
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Old Mar 8, 2009 | 01:19 AM
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seems to me its the alternator isnt charging.. Your running straight off the battery.
do what he said above my post.. try disconnecting your batter while it idles and see if it stays alive, if it does its charging..and check the wire that is held on by a nut to the alternator, make sure its not loose.. also while it idles, disconnect the battery and get a volt/amp meter and check how much your alterntor is putting out.. maybe just buy a new reman alternator at kragen with lifetime warranty..
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Old Mar 8, 2009 | 04:52 PM
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aite ima do it today
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Old Mar 8, 2009 | 06:35 PM
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Try replacing the alt again. Test the alt. first though.

Sometimes it happens.
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Old Mar 9, 2009 | 01:16 AM
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how long did you try to let the alt charge the battery? would let the car run at least 15 minutes.
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Old Mar 9, 2009 | 02:08 PM
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could be just a loose ground on the alternator, I would check that first.
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Old Mar 9, 2009 | 11:06 PM
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Originally Posted by myfc3s
Have you tried to disconnect the negative terminal off the battery while the engine is on? If the engine does stays ON, than your alternator is working but if your engine turns off as soon as you unplug the negative terminal than you Sir have a bad Alternator. As for the battery, i would take that to a local Auto parts store and have them check the CCA and charging defects. Good luck

This is not something you want to do on a fuel injected car, the alternator voltage regulator gets a reference voltage from the battery. When you disconnect the battery, this voltage reference is not there. This can cause the output of the alternator to quickly exceed 18VDC as the battery is missing. If this happens, you are more then likely to fry your ECU. You will also provide your ECU with a huge amount of ripple voltage, which can also damage the unit.

Your best bet is the measure the battery voltage when the car is on. If Battery voltage is 13-15Vdc then alternator is okay, if below 12.8Vdc, your alternator is bad.

Much safer to just measure the battery voltage.
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Old Mar 9, 2009 | 11:12 PM
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From: pomona/socal
Originally Posted by iLikeEatPoo
how long did you try to let the alt charge the battery? would let the car run at least 15 minutes.
i drove itn to work thats like 15 min drive
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Old Mar 9, 2009 | 11:13 PM
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From: pomona/socal
Originally Posted by trainwreck517
This is not something you want to do on a fuel injected car, the alternator voltage regulator gets a reference voltage from the battery. When you disconnect the battery, this voltage reference is not there. This can cause the output of the alternator to quickly exceed 18VDC as the battery is missing. If this happens, you are more then likely to fry your ECU. You will also provide your ECU with a huge amount of ripple voltage, which can also damage the unit.

Your best bet is the measure the battery voltage when the car is on. If Battery voltage is 13-15Vdc then alternator is okay, if below 12.8Vdc, your alternator is bad.

Much safer to just measure the battery voltage.
damn u sound like u went to UTI opr wyo tech lol jk jk thanks for the info tho
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Old Mar 10, 2009 | 02:34 AM
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Actually he sounds like he used the search button.
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