What was found
AFTER APPROXIMATELY 2 HRS AT CRUISE, AUTOPILOT CMD A DISENGAGED ON ITS OWN WITH NO INADVERTENT PILOT ACTION. ACFT BEGAN AA GENTLE 200'-300' CLIMB THAT WAS ARRESTED IN 20. ACFT HAND FLOWN BACK TO ASSIGNED ALTITUDE, RETRIMMED VERY SLIGHTLY, NOSE DOWN. A/P ENGAGE CMD A RESELECTED ON. AUTOPILOT CONNECTED AND FLEW ACFT NORMALLY. NO MASTER CAUTION, NO ABNORMAL INDICATION ON OVERHEAD PANEL. NOTHING IDENTIFIED AS HAVING CAUSED AUTOPILOT TO DISCONNECT. AUTOPILOT CMD A THEN OPERATED COMPLETELY NORMALLY. ACFT GROUNDED. PERFORMED DFCS CURRENT STATUS BITE WITH NO FAULTS FOUND. PERFORMED FAULT HISTORY BY FLT DECK EFFECT ON CHANNEL A FOUND MCP J1A -KO6 FAULT PERFORMED MCP TEST IAW FIM 22-11, TASK 803 AUTO TEST PASSED. ACFT OK FOR SERVICE.