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Q: Loud humming noise

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The battery light icon and check charging system came up, and it's making a loud humming noise. I believe the alternator needs replacing.

The bearing or brushes in your alternator are likely going out. You could also have another issue in your belt drive system causing the noise and lack of charging.

A visual inspection of the drive system, a stethoscope to listen for noise, and a multimeter to test your battery can determine the cause of your car’s issues. I recommend having a certified mechanic, such as one from YourMechanic, diagnose your car’s humming noise and Battery Light to recommend the best path to repair.

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