What was found
EMERGENCY LIGHT ARMED, INOPERATIVE EMERGENCY LIGHT FUNCTIONS NORMALLY IN ON POSITION. PERFORMED EMERGENCY LIGHTING OPS CHECKED & FOUND NR 1 EMERGENCY BATTERY TO BE INOPERATIVE. IAW MM 33-50-00. GAINED ACCESS TO AFT CENTER FLOORBOARD (131BTC) IN COCKPIT & REMOVED NR 1 EMERGENCY BATTERY PACK REPLACEMENT. ALL MX IAW MM 33-50-06. EMERGENCY LIGHT, BATTERY PACK FOUND PART NUMBER INSTALLED, CBS28-2, IS DIFFERENT TO THE PROVIDED BATTERY PACK, 6430028-1. IAW AIPC, THIS PART IS NOT APPLICABLE TO THIS ACFTS SN RANGE. ALL MX IAW MM 33-50-06. INSTALLED NEW EMERGENCY BATTERY ( CBS28-2 SN: 001259) IAW AMM 33-50-06, PERFORMED OPS CHK IAW AMM 33-50-00. NO DEFECTS NOTED.