What was found
WITH EMERGENCY LIGHTS ARMED, SEAT 3 OVERHEAD & TOE KICK LIGHT AS WELL AS RIGHT OUTSIDE WING INSPECTION LIGHT INOPERATIVE. STARTED APU & DID A 30 MINUTE POWER CYCLE, SHUT DOWN THE AIRCRAFT AND THOSE LIGHTS STARTED WORKING AGAIN. THE AIRCRAFT WAS ONLY SHUT DOWN FOR 2 TO 3 HOURS BETWEEN FLIGHTS. REPLICATED FAULT FOR BOTH NR I & 2 EMERGENCY BATTERY PACKS. GAINED ACCESS TO AREAS, REMOVED OLD EMERGENCY BATTERY PACKS, AND INSTALLED CUSTOMER-PROVIDED NEW EMERGENCY BATTERY PACKS. ALL WORK DONE LAW AMM 33-50-06. OPS CHECKED GOOD.