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Q: Squealing noise when A/C is turned on or off

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When I turn on the AC or defrost, there is a very high pitched sound. What should I do?

The noise you hear is the AC compressor belt, most likely. The belt may be loose and just need adjustment, or it may be stretched and need to be replaced. Have a mechanic perform a diagnostic inspection, and replace the AC compressor belt if it is needed, or adjust it.

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