Q: Loud humming noise

asked by on February 19, 2016

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

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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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