What was found
AT 30000 FT BOTH PACK TEMP AND PACK OFF LIGHTS ILLUMINATED, EICAS AUTO EVENT RECORDED. PERF. PACK TEMP. CONTROLLER BITE REF. FIM 21-51 FAULT TREE 803. NO FAULTS. OPERATED BOTH PACKS WITH APU BLEED AIR FOR 1 HOUR REF. AMM 21-00-00. UNABLE TO DUPLICATE FAULTS. PERF. BITE AFTER, STILL NO FAULTS PRESENT. RAN BOTH ENGINES AND OPERATED PACKS BOTH WITH ISOLATION VALVES OPEN AND CLOSED. UNABLE TO DUPLICATE. PERF. BITE AFTER ENG. RUN, NO FAULTS PRESENT. ENG. RUN PERF. BY U346472. REMOVED AND REPLACED RH FLOW CONTROL CARD AS PRECAUTIONARY REF AMM 21-51-09. OPS CK GOOD NO DEFECTS NOTED. BOTH PA OPS CHECK OF BOTH PACKS GOOD.