As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING OVERNIGHT LINE CHECK THE EMERGENCY OVERHEAD EMERGENCY EXIT SIGN ABOVE DOOR 4 RIGHT WOULD NOT ILLUMINATE. MAINTENANCE FOUND BATTERY PACK M736 TO BE DEFECTIVE AND REPLACED IT. SYSTEM OPERATION WAS NORMAL AFTER THE BATTERY PACK WAS REPLACED.