What was found
(CAN) THE TUBE FAILED DUE TO CORROSION. THIS TUBE IS A FREON CARRYING TUBE. THE CORROSION OCCURRED AT THE POINT WHERE THE EXPANSION VALVE SENSING COIL, COPPER, WAS IN CONTACT WITH THE TUBE ASSY, ALUMINUM. CAUSED LOSS OF ALL FREON FROM THE SYSTEM. OIL FROM THE SYSTEM WAS FOUND VISUALLY AT THE EXPANSION VALVE, HOWEVER, THE PIN HOLE WAS DISCOVERED BY PRESSURE TESTING THE SYSTEM. AIRCRAFT MFG IS THE MFR OF THE TUBE. THE TUBE WAS REPLACED AND THE SYSTEM WAS SERVICED.