What was found
WHILE IN CRUISE FLIGHT, AT FL310 AT MACH .86, CABIN PRESSURE DIFFERENTIAL AT 8.6 PSI, THE NOSE GEAR CYCLED DOWN AND UP. HAD RED UNLOCK LIGHT FLASHED MOMENTARILY THEN OUT. ITEM IS UNDER INVESTIGATION. CONNECTED DMU UNIT AND MONITORED LANDING GEAR LOGIC MODULE, REMOVED AND REPLACED UPLOCK ACTUATOR. PERFORMED LANDING GEAR EXTENSION AND RETRACTION, ADJUSTMENT TEST CHECK IS GOOD ALSO EMERGENCY CABLE RELEASE IS GOOD. ALL WORK PERFORMED IAW MM.