As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT GROUNDED. ELECTRICAL SMOKE SMELL @ FL 340. MCP FAILED VNAV AND LNAV. ALL INDICATIONS FAILED TO INPUTS. MCP REMOVED AND REPLACED MCP 22-11-34-004-003 AND -004. DFCS MCP BITE TEST GOOD IAW AMM 22-11-34-745-001. ACFT OK FOR SERVICE. PILOT STATED THAT SMELL DISSAPATED ONCE AUTO PILOT WAS DISENGAGED. APPLIED ACFT POWER TO SYSTEMS FOR 4 HOURS WITH NO SMELL AFTER MCP WAS REPLACED. PERFORMED GVI OF FLIGHT DECK PANELS AND LIGHTING. NO DEFECTS NOTED.