As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
RIC MX - DURING ROUTINE MAINTENANCE, MX FOUND AFT RIGHT WING AND AFT AISLE EMERGENCY LIGHTS INOP. AFTER TROUBLESHOOTING THE SYSTEM FOUND EMERGENCY BATTERY NR 4 NOT HOLDING CHARGE. MX REMOVED AND REPLACED EMERGENCY LIGHT BATTERY. OPERATIONAL CHECK WAS PERFORMED SUCCESSFULLY. ACFT WAS APPROVED TO RETURN TO SERVICE.