What was found
DURING C4/S1 CHECK, INSPECTION REPORTED FWD LEFT AND AFT LEFT EPSU BATTERIES FAILED CAPACITY CHECK. REPLACED EMERGENCY ESCAPE PATH LIGHT BATTERY PACKS, FWD, AFT, MID L AND MID R. OPS CHECKS NORMAL IAW AMM 33-51-38-00-002 AND 33-51-38-400-002.