Auto Air Conditioning & Heater Repair: AC help in 2000 Sable, mercury sable, musty air

Question
2000 Mercury Sable, 24 valve. The AC blows cold air out for the first 5-10 minutes when running. Then turns to a warm, musty air. After shutting it off for about 20 minutes or so, the cold air returns and lasts a couple minutes before turning back to warm and musty. I already changed the cycling switch on the accumulator. That did nothing. Any suggestions are appreciated. Thank you.

Answer
Hi Dave

Disconnect the cycling switch and see if compressor turns off.  If it does not turn off then check wiring for a jump on the wires.  If it turns off then see if your fan (cooling fan) are turning.  If fan is off check fan for power and repair.  If fan is running then you must check your system pressures and see if maybe the pressure is low.  Let me know what you find.