As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING MAINTENANCE BASE VISIT FOUND ALL THE EMERGENCY LIGHTS POWERED BY THE NR 1 BATTERY INOPERATIVE. THE AIRCRAFT WAS REMOVED FROM SERVICE. THE NR 1 BATTERY VOLTAGE WAS NORMAL BUT IT WAS DETERMINED THROUGH NEW BATTERY INSTALLATION THAT THE SUSPECT BATTERY COULD NOT SUPPORT A LOAD. REMOVED AND REPLACED THE NR 1 BATTERY AND CHARGER ASSEMBLY IAW EMB140 AMM 33-50-04. THE OPERATIONAL CHECK OF WAS GOOD. THE AIRCRAFT WAS RETURNED TO SERVICE.