What was found
AUTOPILOT "B" KICKED-OFF TWO TIMES AT CRUISE FLIGHT. SWITCHED TO AUTOPILOT A AND IT WORKED FINE. GROUNDED - YES. REMOVED AND REPLACED FCC B IAW B737-800 AMM 22-11-33-000/400-801. VERIFIED CORRECT SW WAS PREVIOUSLY LOADED. BOTH FCC A+B MATCH OPS. PERFORMED DFCS LRU REPLACEMENT TEST FOR B737-800 FCC IAW B737-800 FIM 22-11 TASK 802. PERFORMED DFCS LAND VERIFY IAW AMM 22-11-00-700-801. ALL TESTS PASS, NO FAULTS. ALSO, PERFORMED HGS SYSTEM TEST IAW SMM 34-36-00 SEC 500, TEST PASS, NO FAULTS.