What was found
AUTOPILOT B DISCONNECTED TWICE IN CRUISE DURING SMOOTH FLYING CONDITIONS. BOTH TIMES IT WAS REENGAGED WITH NO ISSUE. GROUNDED - YES. DFCS FAULT REVIEW SHOWS NUMEROUS FAULT MSG# 22-11607 "MCP DATA INV" & HGS FAULT REVIEW SHOWS "RALT 2" FAULT MESSAGE ON FLT 1,3,4,5,9,13. ACCOMPLISHED B737-800 FIM 22-11 TASK 817 "MCP PROBLEM" FAULT ISOLATION. REMOVED & REPLACED MCP REF B737-800 AMM 22-11-34 & LRRA 2 REF AMM 34-33-21. ACCOMPLISHED MCP INSTALLATION TEST REF AMM 22-11-34-740-801 & AMM 22-11-34/501, FIM 22-11 TASK 802, DFCS LAND VERIFY TEST REF AMM 22-11-00 & HGS SYSTEM TEST REF SMM 34-36-00, OPS CK NML.