Help!! Air Condition doesn't work

[cvcsmkr]

when i got the truck a week agao the ac only worked on HI. yesterday it just konked out(the blower doesn't work, i dont know if the compressor works or not). i already did a search and couldn't find anything. i also have a haynes book but it doesn't say anything about diagnosis or the blower relay. I have replaced the fan speed selector switch but it did nothing. I assume there is some kind of relay for the blower, but i dont know where it is.
Has anybody else had this problem?
Where are the controls for the blower?

 

[SpoolingTurbo6]

this is what i done

this is what i done

What I did was replace the little silver rectangular cube that gose to the

blower box,and the selector switch as well(selector switch is usualy the prob.

it is also a good thought to check presure on ac system the low presure

switch gone out on mine before to