As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING MAINTENANCE, AN OPS CHECK WAS PERFORMED. FWD ESPU BATTERY FAILED DURING BATTERY TEST. EMERGENCY LIGHT WAS FOUND TO BE INOPERATIVE. R & R THE BATTERY PACK IAW AMM IAW 33-51-38. R & R L2 ESPU (10WL) IAW AMM 33-51-38. OPS CHECK PASSED.