As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING PRE-FLIGHT, THE EMERGENCY LIGHTS DID NOT WORK DURING TEST FROM FLIGHT ATTENDANT PANEL. MAINTENANCE REMOVED AND REPLACED THE NR 2 BATTERY PACK AND POWER SUPPLY IAW MM. OPERATIONAL CHECK WAS GOOD AND AIRCRAFT WAS RETURNED TO SERVICE. (SW21200502113) (K)