What was found
DURING MAINTENANCE FOUND THE NR 1, 2, 3 & 4 EMERGENCY BATTERIES REQUIRED REPLACEMENT. THE AIRCRAFT WAS REMOVED FROM SERVICE. REMOVED AND REPLACED THE #1, 2, 3 & 4 EMERGENCY BATTERIES IAW EMB-145 AMM 33-50-04. SERIAL NUMBER 1 105211, SERIAL NUMBER 2 68819, SERIAL NUMBER 370993, SERIAL NUMBER 4 115005. THE OPERATIONAL CHECK WAS GOOD. THE AIRCRAFT WAS RETURNED TO SERVICE.