As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING M-CHECK, SIN MAINTENANCE WAS CHECKING OUT THE UPPER DECK DOOR RIGHT EMERGENCY POWER RESERVOIR FIRING TEST, AND FOUND BATTERY OK LIGHT DID NOT ILLUMINATE. MAINTENANCE REMOVED AND REPLACED BATTERY PACK AND SUPPLY UNIT. OPERATIONAL CHECK GOOD.