As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
MCP APPEARED TO FAIL UNABLE TO CONTROL ALT SHOWED 50000FT TO TOU CH DOWN REMOVED, REPLACED, AND OPS TEST DFCS MODE CONTROL PANEL AS PER AMM 22-11-34. INSTALLATION TEST PASSED.LAND VERIFY BITE HAS TO BE PERFORMED DUE TO REPLACEMENT OF THE AUTOPILOT MODE CONTROL PANEL. PERFORMED LAND VERIFY BITE AS PER AMM 22-11-00. LAND VERIFY PASSED. AIRCRAFT REMAINS FULL CAT 3A CAPABLE.PARTS USED: 29-2211-9-0009, QTY :1 ROTABLE PARTS CHG:TT # 1445632 SN OFF 6385 PN OFF 29-2211-9-0009.PANEL, CONTROL, OFF 29-2211-9-0009 6385 ON 29-2211-9-0009 8111