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Q: Rattling noise AC heater

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I heard a very loud rattle coming from behind my glove compartment when I turn on the air conditioner or heater in my car. I checked the fan motor and everything seems fine. I took a look at the re circulating function and it’s fine, too. Do you know what might be causing the rattling noise?

A: Hey there, thanks for writing in about your...

Hey there, thanks for writing in about your 2010 Lexus HS250h. Even though you said the blower motor looks okay, my guess is that it probably has a bad bearing, which is causing the noise. The only other thing I can think of is the blend door actuator, but that would be more of a clicking noise. Have a professional, such as one from YourMechanic, inspect the noise firsthand in order to determine the cause of the problem.

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