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Q: Possible alternator problem

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How can I tell if the alternator needs to be replaced?

Hi. An illuminated dashboard charging light is almost a sure sign that the alternator needs to be replaced. If the light is not on and you suspect a problem with the alternator, there are a few ways to test it. One way is to check charging system output with a digital multimeter. The other is to test the starting/charging system with a professional digital test machine. The second way is the easiest and is the most comprehensive. If you need further assistance, I recommend you have a certified technician, like one from YourMechanic, diagnose the starting issue and replace any failing parts.

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