As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
EMEGENCY POWER PACK, M1670, FAILS EMERGENCY LIGHTING FUNCTIONAL CHECK. BATTERY DISCHARGES IN LESS THAN 5 MINS (REF AAR NR 99965141) REMOVED AND INSTALLED NEW BATTERY PACK (M1670) AND PERFORMED OPERATIONAL TEST GOOD IAW B737 AMM 33-51-06-960-805.