heater blower???

oaky lets say that this is the switch for the heater in my hatch:
0 -off- off
1 -low- nothing happens
2 -medium- nothing happens
3 -high- fan works
4 -full blast- fan works

so is anyone following that???... if you do know what im talking about can you tell me why number 1 and 2 arent working when i switch to it?
My fuses are good and the blower motor seems to be running fine.
What would i have to replace?

Thanks.

your resistors are damaged. they lower the power that goes to the blower and make it spin slower.

your resistors are damaged.

can you explain where they are and what i need to replace it?