What was found
CABIN EMERG LIGHT: DURING EMER LIGHT PREFLIGHT CHECK THE FLOOR EMER LIGHT ON SEAT 3 WAS OFF AS WELL AS THE RIGHT FUSELAGE EMER LIGHT. WE RAN TWO 30 MINUTE RECHARGE CYCLE ATTEMPTS. WITH THE SAME FAILURE AFTER EACH CYCLE. CHARGED EMER. BATTERIES IAW TC-FLT-33-1001. SEAT #3 AND AND RIGHT WING INSPECTION LIGHT ONLY STAYED ON FOR 2 SECONDS. #2 BATTERY PACK NEEDS REPLACED. REMOVED AND REPLACED #2 BATTERY PACK UNDER SEAT 3 IAW CE-680A MM 33-50-06.CHARGED FOR 2HRS AND OPS CHECK GOOD. REMOVED P/N:CBS28-1 S/N:009146 INSTALLED P/N:CBS28-1 S/N:2093M