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How do you tell if your alternator is bad?

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Answered 2015-06-14 17:00:30

If the voltage metere is moving up and down there a good chance that its the alt. You can also place a volt meter on the battery while the motor is running (with every thing off), look and the voltage, then turn your A/C on high, turn your lights, wipers, radio ON, if the voltage goes below 12.5, there a good chance that it is bad.

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