What was found
ON CLIMBOUT "STAB OUT OF TRIM LIGHT" LIGHT ON CONTINUOUSLY WITH AUTOPILOT ON. AUTOPILOT WOULD NOT TRIM OR HOLD ALTITUDE. RAN " STABILIZER OUT OF TRIM LIGHT REMAINING ILLUMINATED" CHECKLIST TWICE. AUTOPILOT WOULD NOT ENGAGE PROPERLY WITH A/P DISCONNECTED, ALL TRIM SEEMED TO WORK PROPERLY. MADE DESCENT AND LANDING WITH A/P DISENGAGED. AACFT WAS IN SERVO "A" AT THE TIME. RELEASED FOR SERVICE IAW MEL: 22-01-11-A. REMOVED AND REPLACED A/P MODE CONTROL PANEL IAW MM 22-11-181-4. PERFROMED A/P RTS CKS IAW MM 22-11-008-5. NO DISCREPANCIES NOTED. A/P SERVO "A" REMAINS NOT II. SERVO "B" IS CK II.