What was found
EXIT LIGHT ON EXTERIOR LAV WALL, EXIT LIGHT ON LAV KICK PANEL AND FLOOR LIGHT UNDER KICK PANEL DID NOT ILLUMINATE DURING CHECK. EMERGENCY LIGHTS BATTERY PACKS CHARGED FOR 1 HOUR PER AFM AND STILL FAILED CHECK. LIGHTS WILL ILLUMINATE ON SHIPS POWER. CORRECTIVE ACTION; REMOVED #4 BATTERY PACK AND INSTALLED NEW #4 BATTERY PACK IAW RADIANT POWER INSTRUCTIONS SIL-CBS28-1-2024-001 REV A. OPERATIONAL CHECKED GOOD PUT AIRCRAFT BACK TO ORIGINAL CONFIGURATION IAW CE680A AMM CH. 33-50-00.