As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PASSENGER CABIN, EMERGENCY LIGHT BATTERY PACK M1672 FAIL FUNCTIO NAL TEST (REF AAR NR 1000032889). REMOVED AND REPLACED BATTERY PACK AT POSITION M1672 AIW B737 AMM 33-51-06-960-805. INSTALLATION TEST OK. FAILED FUNCTIONAL CHECK DURING RELIABILITY CHECK IN RFD REMOVED AND REPLACED BATTERY PACK AT POSITION M1672 AIW B737 AMM 33-51-06-960-805. INSTALLATION TEST OK.