As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AUTOPILOT B DISENGAGED DURING DESCENT. WOULD NOT RE ENGAGE NO OTHER LIGHTS OR WARNINGS ENGAGES AUTOPILOT A NO ISSUES. GROUNDED - YES. PERFORMED DFCS BITE REF B737-800 FIM 22-11 TASK 801 FOUND FAULTS FOR MCP CHAN A+B 22-11607. DUE TO INSTALLED MCP S/N 01687669 HISTORY OF A/P FAILURES REPLACED MCP REF B737-800 AMM 22-11-34/401 ALL REQUIRED TESTS PASSED. NO ACTIVE FAULTS NOTED.