Hello,
Grab a bright flashlight and open your engine compartment hatch and try to really locate the exact location of the noise while the car is running.
After that, turn the car off and make a physical examination of the fan belt area to make sure that nothing has come loose or a stick, twig has not slid into a position that would make contact with something resulting in a high pitched noise.
It worked for me, something came loose and was rubbing against the fan...I was lucky, I hope you are too
Vysoc