Friends - 1992 300TE, quick question on the AC. The system charge is a bit low (bubbles showing on drier), but the compressor does come on. HOWEVER, the Aux Fans do not engage. The electrical dwgs show a pressure switch in the Aux Fan circuit. Should the fans come on whenever the compressor does, or is this a situation where there's enough pressure for compressor engagement but not the Aux Fans (meaning fan resistor might be suspect).

THANKS

Brian