As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WITH ELECTRICAL POWER OFF THE EMERGENCY LIGHTS IN THE AFT ACCESSORY BAY ARE ON. TURNING MAIN AIRCRAFT BATTERY SWITCH ON CAUSES LIGHTS TO GO OFF. LIGHT RETURNS ON WHEN BATTERY SWITCH IS OFF. INSTALLED SERVICEABLE 8130 BATTERY PACKS IN B5-27 AND B5-28 POSITIONS, SYSTEM OPERATIONS TESTS GOOD.