Why is my Ford Focus making a strange noise when I turn on the AC?

I recently purchased a used Ford Focus and have noticed that whenever I turn on the AC, there is a strange noise coming from the engine. It seems to be getting louder and more frequent. Is this something I should be concerned about? How can I fix it?

This could be a sign of a faulty AC compressor. I suggest taking your Ford Focus to a trusted mechanic and having them inspect and possibly replace the AC compressor if necessary.

It could also be a problem with the belt or pulley that connects to the AC compressor. Make sure to have the belt and pulley checked as well.

I've had this issue before with my Ford Focus. Check your AC filter and make sure it's not clogged, that could also be causing the noise.