What was found
MIA - INFLIGHT T922/04 AT ROW 12 SEAT-F SMOKE APPEARED TO COME FROM FLOOR VENT. ACRID BURNED WIRE ODOR ACCOMPANIED SMOKE. POWER PORT WAS NOT SOURCE OF SMOKE. TURNED OFF UTILITY BUSS AND RECIRCULATION FANS. SMOKE AND ODOR DISSIPATED. LANDED MIA WITHOUT INCIDENT. FOUND RIGHT RECIRCULATION FAN FAILURE. REPLACED RIGHT RECIRCULATION FAN. SYSTEM GROUND CHECKED NORMAL OPERATION.