What was found
(CAN) ON APPROACH THE CREW SELECTED LANDING FLAPS. THE FLAPS EXTENDED TO LANDING POSITION (35 DEGREES), BUT THE RIGHT INBOARD FLAP PANEL STAYED RETRACTED. MAINTENANCE FOUND THE RIGHT INBOARD FLEX DRIVE CABLE SWAGED END HAD SLIPPED ON THE CABLE END, ALLOWING THE CABLE DRIVE END TO BECOME DISCONNECTED FROM THE FLAP ACTUATOR. MAINTENANCE THEN FOUND THAT THE SPLIT FLAP SWITCH WAS CONTAMINATED INTERNALLY WITH WATER, WHICH WHEN FROZEN, CAUSED THE SWITCH AND THE FLAP ASYMETRY PROTECTION SYSTEM TO BE INOPERATIVE.