What was found
MAINTENANCE REPORTED WITH AIRCRAFT POWER OFF (OR IN GROUND POWER), SEATS 18, 14, 12 AND ALL OF AFT GALLEY EMERGENCY LIGHTS WILL NOT TURN ON. WITH AIRCRAFT POWERED UP, ALL OPS CHECK GOOD. MAINTENANCE REMOVED AND REPLACED BATTERY PACK AT 13WL. OPS CHECK GOOD PER AMM 33-51-38.