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AC light flashing, but AC working fine

2000 Camry (4 cylinder) - the AC light started flashing, but the AC is still blowing cold air. There is a bit of noise (sort of a deep whine) that wasn’t there before it started flashing and I hear the noise even when the AC is off. Any ideas?

A flashing AC light means that the compressor didn’t rotate at the speed that the climate control module commanded.

This is usually caused by a loose/worn serpentine belt.

Tester

Is there any way to tell if it’s worn? And will it damage anything if I don’t replace it. (I was just at a mechanic and assume, but I’m not sure, that he checked whether the belt was loose.)

A broken serpentine belt won’t do much damage. Unless you want your alternator, power steering, and possibly water pump to keep working. That’s all.

Yes, go get the belt checked.

It can be determined of a serpentine belt is loose. But it can’t be determined if a serpentine belt is worn by looking at it.

This video explains this.

Tester