I just purchased a used 2004 IS300, and i didn't realize it at first, but there is a high pitched whine coming from the right side of the cabin, close to the glove box. The whine comes on when i turn the fan on every setting other than full blast. The air conditioner does not affect the noise. I think it might be the electrical resistor that alters the fan speed. Has anyone had this problem before? or anyone have any ideas, it is getting really annoying. Thanks.

 

listen to the noise as u change the speed of your fan it will probably change with the fan speed. 99% of the time its the blower motor located right behind your glove box. its held in by 3 8mm screws behind/below your glove box.