As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
EMERGENCY LT CAPACITY TEST FND L4 CEILING EMERGENCY LIGHT ILLUMINATE TIME LESS THAN 15 MIN SPEC NR B777-33-3-7019 REF NON-ROUTINE N O.9483874. REPLACED DR L4 THE EMERGENCY LIGHT POWER SUPPLY CHARGER AND BATTERY PACK, AND PERFORMED THE TEST. THE RESU LIGHT FOUND NORMAL. REF AMM 33-51-06-960-802 REV 86 & AMM 33-51-06-9 60-803 REV 86.