As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHILE DESCENDING IN A HOLDING PATTERN, THE FLIGHT CREW NOTICED AN ELECTRICAL BURNING ODOR IN THE FORWARD CABIN AND FLIGHT DECK. AFTER SMOKE WAS VISUALLY DETECTED ON THE FLIGHT DECK, AN EMERGENCY WAS DECLARED. COM PROCEDURES WERE FOLLOWED DURING WHICH THE ODOR DISSIPATED. LANDING WAS UNEVENTFUL. MAINTENANCE REPLACED THE NR 1 EQUIPMENT COOLING FAN, OPERATIONAL CHECK OK.