What was found
DURING DESCENT FROM FL410 TO FL310 THE CREW RECEIVED A PITCH TRIM AMBER ANNUNCIATION ON THE PFD'S AT AROUND FL320. AUTOPILOT WAS DISCONNECTED. MANUAL AND ELECTRIC PITCH TRIM WAS UNRESPONSIVE. EMERGENCY WAS DECLARED AND CHECKLIST FOLLOWED. AS THE AIRCRAFT DESCENDED TO LOWER ALTITUDES THE PITCH TRIM STARTED WORKING NORMAL. LANDING WAS UNEVENTFUL. MAINTENANCE REPLACED BOTH TRIM ACTUATORS AND THE PITCH TRIM ELECTRIC MOTOR. EMPENNAGE DRAIN HOLES WERE INSPECTED FOR OBSTRUCTION. A SUCCESSFUL OPERATIONAL CHECK FLIGHT WAS PERFORMED WITH NO DEFECTS NOTED. AIRCRAFT WAS RETURNED TO SERVICE. L/H PITCH ACTUATOR PN OFF: 6660161-13, SN OFF N/A. RIGHT PITCH TRIM ACTUATOR PN OFF: 6660161-14, SN OFF: N/A.