I get a hi pitch sound when AC is on whist driving. I thought it might be the fan motor or fan bearing. Has anyone else experienced this before please?

 

This is not much to go on?
Did you pop the hood and is the sound coming from there OR was the sound on the passenger side under the glovebox?

IF you have the blower on full and AC on and then only turn the AC off does the sound remain or

if you adjust the for front defrost on and full blower speed is the sound under the hood or under the dash??


etc., etc., etc.


little more information will help?

The other thing is all reading this, when you ask for help PLEAS tell use the basic and minimum information miles and year and anything that you would normally fill out as vehcle information as if you went to a service shop about your Mazda!