As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHILE ACCOMPLISHING GROUND CHECKS, THE FLIGHT CREW FOUND EMERGENCY LIGHTS WOULD NOT TEST. GROUND MAINTENANCE INVESTIGATED AND DETERMINED THE BATTERY POWER SUPPLY WAS INOPERATIVE. THE BATTERY POWER SUPPLY WAS REPLACED IAW DC-10 MM 33-51-01. (X)