As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
TYR - FLT 3738 - DURING PRE-FLIGHT, THE FLIGHT ATTENDANT INFORMED THE CREW THAT TWO EMERGENCY LIGHTS WERE INOPERATIVE. AIRCRAFT WAS FERRIED TO DFW FOR MAINTENANCE. MAINTENANCE REMOVED AND REPLACED THE BATTERY PACK IN POWER SUPPLY UNIT 21LN. OPS CHECK WAS GOOD AND AIRCRAFT WAS RETURNED TO SERVICE. (M)