Well if I had to take a stab at it I would look for a frozen evaporator.If refridgerant can't pass thru the evaporator it can't boil away the moisture in the air.Second thing I would look at is the placement of the temp prob.If it has moved or fallen out of the evaporator it cant sense evap temp and shut down the compressor.Third thing would be to check the expansion valve.sometimes they do get plugged with desicant from the accumulator or drier.