As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE CREW REPORTED THAT NOT ALL EMERGENCY LIGHTS ILLUMINATE WHEN THE SYSTEM TURNS ON, WITH THE FOLLOWING BEING INOP.; REAR PART OF EXIT ROW O/HEAD SIGN, BOTH SIDEWALL EXIT SIGNS ON LEFT SIDE, ONLY WALL SIGN ON RIGHT SIDE EXIT ROW. MAINTENANCE INSPECTED THE AIRCRAFT AND REMOVE AND REPLACED THE AFT BATTERY PACK FOR THE EMERGENCY LIGHTS, OPERATIONALLY TESTED WITH NO DEFECTS AND THE AIRCRAFT WAS APPROVED FOR RETURN TO SERVICE.