What was found
CARGO BTL LOW CAUTION MESSAGE IN CRUISE. RAN QRH AND LANDED AT NEAREST SUITABLE AIRPORT. (FLT#3500) CLOSED UPON INVESTIGATION OF RIGHT HAND CARGO FIRE BOTTLE BEING RELEASED, ALSO FOUND THE RIGHT HAND 14TH STAGE DUCT ASSY INSULATION WAS BLOWN APART DUE TO THE AFT CLAMP OF THE 14TH STAGE SHUTOFF VALVE BEING LOOSE. REMOVED AND REPLACED THE 14TH STAGE DUCT ASSY IAW AMM. LEAK AND OPS CHECK GOOD, NO DEFECTS NOTED. A/C OK FOR SERVICE.