What was found
WHILE DESCENDING FROM FL370 TO FL350 A/T DISCONNECT OCCURRED. THIS WAS FOLLOWED IMMEDIATELY BY A RAPIDLY RISING CABIN ALTITUDE. MAX CABIN ALT REACHED 9400-9500 FT. INITIATED EMERGENCY DESCENT. PRESSURIZATION RETURNED TO NORMAL AT 10,000 FT LEVEL OFF. ACCOMPLISHED VISUAL CHECK OF PACK DUCTS & LEAK CHECK INCLUDING CHECK OF BELLOWS. PRESSURIZED A/C MANUALLY IAW CABIN PRESSURIZATION. FUNCTIONAL TEST AMM 21-31-720-802 STEP F1-G2. NO LEAKS NOTED. PERFORMED ENG 1 & ENG 2 ENGINE BLEED OPERATIONAL TEST IAW AMM 36-11-00-710-801-A ENG 1 & ENG 2 BLEED SYSTEMS OPS CHECK OK. AUTO THROTTLE SYSTEMS HZ, OPS CHECK OK IAW AMM 22-31-00-710. REMOVED AND REPLACED CPCS CONTROLLER PRECAUTIONARY PER AMM 21-31-01. FUNCTIONAL