What was found
EMERGENCY LIGHTS REMAINED ON AFTER AIRCRAFT POWER DOWN, EMER LIGHT SWITCH IS IN OFF POSITION, G SWITCH RESET WAS ALSO ATTEMPTED. POWERED UP AIRCRAFT WITH APU POWER. FOUND AFT LT CABIN SEAT OVERHEAD LIGHT AND EXIT SIGN LIGHT ABOVE LAV REMAINED ILLUMINATED WITH EMERGENCY SWITCH IN THE OFF POSITION. RESEARCHED EMERGENCY LIGHTING ADJ/TEST AMM. FOUND NR 3 EMERGENCY LIGHTING BATTERY PACK INERTIA SWITCH HAD TRIPPED. RESET, REMAINING EMERGENCY LIGHTS EXTINGUISHED. POWERED APU FOR ANOTHER 60 MINS TO FULLY CHARGE THE REMAINING EMERGENCY BATTERY PACKS. SYSTEM OPS CHECK NORMAL WORK PERFORMED IAW AMM 33-50-00.