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crazy 'check charging system' indicator

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crazy 'check charging system' indicator

Old 09-24-2018, 01:36 PM
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Join Date: Apr 2007
Location: ca
Posts: 27
Default crazy 'check charging system' indicator

I've read a bunch of posts about this, but I have a question about the duration. I got a new battery more than 3 months ago, and immediately started getting the red battery light and the 'check charging system' indicator. Every time I drive this happens. I clear it, and sometimes it comes back, but most of the time it doesn't happen again during that particular drive. I verified all my connection are OK. I'm going on 4 months with this. The battery turns over really fast when I start the car. It's showing no signs of weakening. Question: How long does it take for the battery to ruin my alternator or the alternator to ruin my battery, or is the warning meaningless?
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Old 09-24-2018, 01:42 PM
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Location: AZ
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Your alternator is going out. The "check charging system" warning comes up when the alternator fails to output at least 12.5 volts. Depending on how far it dips and for how long, it can take months to ruin a battery or a few days. Get a volt meter next time the light is on and check the voltage at the battery. A good alternator will output between 13.5 and 14.2 volts. Anything less than that and the alt is going bad.

I picked up a brand new alternator on Amazon by TYC for about $120. It's been 6 months now and is working flawlessly in the AZ heat.
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Old 09-24-2018, 01:56 PM
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Join Date: Apr 2007
Location: ca
Posts: 27

Thanks - I'll head over to Autozone later and check for the numbers you provided. I've noted the Amazon link as well.

Last edited by lmarlo; 09-24-2018 at 01:59 PM.
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Old 09-24-2018, 03:10 PM
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Alternator MUST put out 13.5+ to charge the battery. 12.5 is still too low!
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