What was found
FLT JB1424 - DURING CRUISE AT 36,000 FT CABIN ROSE TO 8800 FT IN AUTO MODE, SWITCHED TO MANUAL AND DESCENDED TO 34000. CABIN ALTITUDE DESCENDED BELOW 8000 FT & SELECTOR WAS RETURNED TO AUTO, ENTIRE SEQUENCE REPEATED AT 34000 & 32000 FT. NORMALLY BOTH CHANNELS OF CPC & MANUAL MODE DID NOT RESPOND TO OUTFLOW VALVE INDICATION ON MFD WAS FULL CLOSED AT ALL TIMES. PER ENGINEERING, MX R & R NR 2 PACK FLOW CONTROL VALVE IAW AMM 21-51-01, OPS CHECK GOOD. R & R PACK NR 2 OUTLET TEMP SENSOR IAW AMM 21-51-18/401. ACCOMPLISHED BLEED SUPPLY ADJUST TEST IAW 36-11-00-05, NO FAULTS NOTED. AS PER ENGINEERING, INSPECTED RT BLEED PRESSURE SENSOR TUBE & FOUND MOISTURE INSIDE. CLEANED TUBE, CLEARED PACK NR 2 MDDR 68919. ACFT RETURNED TO SERVICE.