As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT NOT GROUNDED - AFT SECTION EMERGENCY AND EXIT LIGHTS WILL NOT ILLUMINATE. REMOVED AND REPLACED EPSU (EMERGENCY POWER SUPPLY UNIT) 13WL (AALA202009039014) AND EPSU BATTERY (AALA202009039018) PER AMM 33-51-38, OPERATIONAL TEST NORMAL.