As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON FLIGHT 2983 THE CREW REPORTED A PTRIM MAIN INOPERABLE WARNING MESSAGE ON EICAS. THE CREW FOLLOWED AOM VOL 1 DESELECTED MAIN SYSTEM CUTOUT, THE BACK UP SEEMS TO WORK. THE CREW DECLARED AN EMERGENCY AND LANDED WITHOUT INCIDENT. THE AIRCRAFT WAS REMOVED FROM SERVICE. REMOVED AND REPLACED THE HORIZONTAL STABILIZER CONTROL UNIT HSCU IAW EMB AMM 27-40-01. THE OPERATIONAL CHECK WAS GOOD IAW EMB AMM 27-40-00. THE AIRCRAFT WAS RETURNED TO SERVICE.