What was found
WITH BATTERIES OFF AND NOT ON SHIP POWER, EMERGENCY LIGHTS DO NOT COME ON WHEN SWITCHED TO THE ON POSITION. EMERGENCY LIGHTS DO COME ON WHEN SWITCHED TO THE ARM POSITION, WHEN NOT ON SHIP POWER. ONCE EMERGENCY LIGHTS HAVE TURNED ON WITH THE SWITCH IN THE ARM POSITION, THEY WILL STAY ON IF THE SWITCH IS TURNED TO ON. WHEN ON SHIP POWER (BATT ON, OR BATT AND GPU ON, EMER BUSSES POWERED), EMERGENCY LIGHTS WILL TURN ON WITH THE EMERGENCY LIGHT SWITCH IN THE ON SWITCH POSITION. EMERGENCY LIGHTS BATTERY PACKS HAD TIME TO FULLY CHARGE. SUSPECT THE NUMBER THREE EMERGENCY LIGHT BATTERY IS FAULTY. CORRECTIVE ACTION; REMOVED AND REPLACED AFT EMERGENCY BATTERY PACK !AW CE700 AMM 33-50-05, PERFORMED OPERATIONAL CHECK IAW CE700 AMM 33-50-00. OPS CHECKS GOOD