What was found
AMBER, CABIN ALTITUDE, CAS MESSAGE WAS REPORTED ON A SUBSEQUENT FLIGHT. MAINTENANCE TECHS TROUBLESHOT THE SYSTEM AND FOUND A FAULTY PRIMARY OUTFLOW VALVE. THE VALVE, PN 103678-3, WAS REPLACED WITH AN O/H UNIT. LEAK AND OPS CHECKS WERE NORMAL AND THE ACFT WAS RETURNED TO SERVICE.