Nissan Repair: AC Problem 2002 nissan frontier, nissan frontier, receiver dryer

Question
Currently the heater/ac fan only works on high.  Also when I first put the AC on in the morning it works fine, but after I drive a few mile it starts to squeal so I have to turn it off.  After awhile I turn it back on still squeals but now blows hot air,

Answer
Charles,

You have two problems here.  First, replace the resistor for the blower motor.  It is located under the dash, passenger side.  The second is it sounds like your compressor is locking up and this will require replacement of the compressor and receiver dryer.  Then have it evacuated and charged.