As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
MCP BUTTONS STICK AND TAKES SEVERAL PUSHES OF HDG SEL AND LNAV BUTTONS TO GET THEM TO ACTIVE MODE WITH A GREEN LIGHT. GROUNDED - YES. REPLACED MCP WITH SERVICEABLE ONE. ACCOMP MCP INSTL TEST, TEST PASS. ALSO ACCOMP DFCS MCP REPLACEMENT TEST & LAND VERIFY TEST FOR LLM TESTS, TEST PASS REF B737-900 AMM 22-11-34-400-801 & AMM 22-11-34, & AMM 22-11-00.