Blower Switch
WARNING: This page is about a different car, the 2002 GMC Safari and 2002 Chevrolet Astro. However, it is still accessible from the selected car via links, so may be relevant.
Blower switch is a 4-position knob with LO, 2 medium speeds and HI position. See Figure. Blower motor operates in all positions. Auxiliary A/C-heater blower switches are 4-position units with OFF, LOW, MED and HIGH positions.