blower motor resistor?
 

2004 hatchback automatic. while driving, the a/c compressor will turn off and on intermittently. the fan continues to run at whatever speed it is set on, just no cold air. had the refrigerant checked-it is exactly where it needs to be. shop told me blower motor resistor, but i had one of those go bad in my truck years ago and it would cause the blower fan to quit, not the compressor. i was wondering if a switch on the a/c system would cause it to do this. if it wasn't such a p.i.t.a. to change the resistor i'd have just done it, but if i go to the trouble of pulling the whole dash apart and that's not the problem i'll probably get rid of the car.

Same experience here. 2004 sedan, 5-spd.
I've done everything, including changing out the A/C switch twice with no good solution.
Still turns off intermittently.
However, if I wiggle the blower switch between positions and back, the A/C will come back on again - at least for a while.

i had found a post by someone saying the blower motor fan switch was prone to going bad. it was about $32 at mazda, so i figured i would try that first. that was the problem! it was a little bit of a p.i.t.a. to change, but much better than pulling out the dash.