As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) ON APPROACH WHEN THE CREW SMELLED SOMETHING BURNING IN THE CABIN. THE CABIN FILLED UP WITH SMOKE AND THE CREW PUT ON THEIR MASKS AND DROPPED THE PASSENGERS MASKS. THEY LANDED WITHOUT DECLARING AN EMERGENCY. AN AME WAS SENT TO AND DETERMINED THAT THE DEFOG FAN WAS AT FAULT. THE FAN WAS DEFERRED AND WILL BE REPLACED ON ITS RETURN. (TC NR 20070123004)