As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON FLIGHT 4234 THE CREW REPORTED A VERY STRONG ELECTRICAL BURNING ODOR IN THE COCKPIT AND FORWARD CABIN. THE AIRCRAFT WAS REMOVED FROM SERVICE. PERFORMED FIM TASK 21-20-00-810-801-A. FOUND NR 1 RECIRCULATION FAN INOP. REMOVED AND REPLACED THE NR 1 RECIRCULATION FAN IAW EMB 145 AMM 21-24-01. THE OPERATIONAL CHECK WAS GOOD. THE AIRCRAFT WAS RETURNED TO SERVICE.