As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT EN ROUTE FROM MDW TO MYGF AT FLIGHT LEVEL 45,000FT WHEN CREW NOTICED SMOKE COMING FROM OVERHEAD VENT. CREW DECLARED AN EMERGENCY AND INITIATED AN EMERGENCY DESCENT INTO SDF. THE CREW DISENGAGED CABIN VENTILATION WHICH CAUSED SMOKE TO CEASE. CONTINUED WITH DESCENT INTO SDF WITH NO FURTHER PROBLEMS. MAINTENANCE FOUND COCKPIT BLOWER MOTOR TO BE THE CAUSE OF SMOKE, REMOVED AND REPLACED MOTOR, OPS CHECKS GOOD.