As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: AN EMERGENCY WAS DECLARED AND THE AIRCRAFT DIVERTED TO BOS DUE TO A BOTTLE 2 DISCHARGE ENGINE EICAS MESSAGE. MAINTENANCE REPLACED THE #2 ENGINE FIRE EXTINGUISHING BOTTLE AND ACCOMPLISHED A SATISFACTORY OPERATIONAL CHECK.