'99 HVAC Fan Control on strike

My 1999 Silverado HVAC fan control is acting up... The fan control knob will shut the unit off, and it works in position 3, 4, and 5. It doesn't work in position 1 or 2.

When I turn the control to position 1, from the off position, the a/c light will light, but the fan does not blow. The fan works fine in position 3, 4, and 5.

Any suggestions on what needs fixed? I'm thinking the switch may be going bad, or maybe the fan motor resistor... Any advice?

Andy C

probably the resistor have seldom seen a manual switch go bad.
resistor is under passenger side of dash in hvac box on bottom left next to blower motor take it out and look a circuit bord can usually see burnt circuit on board

I would check the switch, or eithr the blower motor itself. I've seen several of the switches go bad in my friends' rides.

replaced the switch in my 2001. Very simple to replace and if I recall only about $20 from the dealer.