>>Bad switch right? I just had the system recharged last week, and I can see bubbles go by in the window on the dryer...
>>

The only way to verify pressure switch is with a gauge reading on the high side. Foam/bubbles in quanity at sightglass indicate low refrigerant . Which will not allow the system to reach high side pressure needed to trip aux fan low speed circuit.
Some guys run a cabin sw across the sw so they can regulate the low fan to their liking.
remember , aux fan only comes on at high thermal load, meaning there are time [low ambient temps/low thermal load] , that the fan circuit is not being called for...this is NORMAL...