What was found
DURING MAINTENANCE BASE INSPECTION FOUND BOTH REAR OVERWING EMERGENCY LIGHTS INOPERABLE. THE AIRCRAFT WAS REMOVED FROM SERVICE. REMOVED AND REPLACED BOTH REAR OVERWING EMERGENCY LIGHT BULBS IAW EMB 145 AMM 33-50-07 DID NOT FIX. TROUBLESHOT IAW EMB 145 WIRING MANUAL 33-50-50. FOUND NR 4 BATTERY POWER SUPPLY TO BE BAD. REMOVED AND REPLACED THE NR 4 BATTERY POWER SUPPLY IAW AE W/C 33-700-19. THE OPERATIONAL CHECK WAS GOOD. THE AIRCRAFT WAS RETURNED TO SERVICE.