As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHILE IN-FLIGHT, THE PILOT NOTICED SMOKE AT THE CABIN OVERHEAD. AFTER MAKING PRECAUTIONARY LANDING, IT WAS NOTED THAT THE INSTRUMENT CIRCUIT BREAKER HAD POPPED. INVESTIGATION BY MAINT. REVEALED THAT THE LIGHTED PANEL HAD INTERNALLY SHORTED. THE PANEL WAS REPLACED AND NO FURTHER DISCREPANCIES WERE FOUND.