Q: Rattling noise AC heater

asked by on August 23, 2016

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?

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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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