As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT NOT GROUNDED: MAINTENANCE REPORTS WHILE ACCOMPLISHING TEST OF EMERGENCY LIGHT, GOT FAULT : ATA 335100 BAT / EPSUC (14 WL) MID R. REMOVED AND REPLACED BATTERY UNIT OF 14WL. OPS TEST AND BITE TEST GOOD IAW AMM 33-51-38-400-002-A.