As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FOUND EMERGENCY LT POWER SUPPLY BATTERY (M5170) AT STA 550 WL323 LBL 83 FUNCTIONAL FAIL(<P>IAW AMM 33-51-04-902-001-001 REV 107 REMOVED AND SENT THE BATTERY FOR REPAIR, AFTER THAT, INSTALLED THE BATTERY AND PERFORMED POWER SUPPLY TEST. THE TEST RESULT WAS GOOD.</P>)