My teenage son has a 1987 Mazda B2000 pickup. It recently developed a problem with the A/C. Starting at the fan speed in the off position and the A/C dash buton pushed "On": turn the fan speed up 1 notch. A/C compressor turns on, but fan doesn't run. Turn fan speed up to the next notch, AC compressor still on, still no fan. Turn fan speed up one more notch, fan comes on but A/C compressor turns OFF! Turn up one more notch (high speed), fan runs but A/C is still off. I replaced the fan speed controller switch (the switch attached to the dash knob) but it still does the exact same thing...so I'm assuming the problem isn't in fan speed switch. What else could make the fan not run on 2 notches, and the A/C not run on 2 notches??? Any help anyone could give would be GREATLY appreciated! Thanks.