As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING MAINTENANCE INSPECTION FOUND THE EMERGENCY POWER SUPPLY NR 4 AND THE EMERGENCY CHARGER ASSEMBLY NR 4 INOPERABLE. THE AIRCRAFT WAS REMOVED FROM SERVICE. REMOVED AND REPLACED NR 4 EMERGENCY POWER SUPPLY AND THE REMOVED AND REPLACED NR 4 EMERGENCY BATTERY CHARGER ASSEMBLY IAW AMM 33-50-04 IAW AMM 33-50-04. THE AIRCRAFT WAS RETURNED TO SERVICE.