HVAC Squeeling noise

I have a 96 S10 Blazer 4dr 4wd. When i turn the heater or a/c or blower on, it produces a high pitched squeel. happens no matter what the dials are set to. is there a belt that runs the blower for the HVAC that needs replacing or could this be something more serious???:rolleyes:

I have a 96 S10 Blazer 4dr 4wd. When i turn the heater or a/c or blower on, it produces a high pitched squeel. happens no matter what the dials are set to. is there a belt that runs the blower for the HVAC that needs replacing or could this be something more serious???:rolleyes:

The blower mortor is all electic motor.
Does the squeal change with different blower speeds?

Does engine speed change squeel like a belt slipping?
Have you tryed unplugging the AC compressor?