As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING AN OVERNIGHT LINE CHECK, THE EMERGENCY EXIT SIGN FOR DOOR FOUR RIGHT WAS INOPERATIVE. MAINTENANCE FOUND THE ASSOCIATED POWER SUPPLY MODULE TO BE THE PROBLEM AND REPLACED IT. SYSTEM OPERATION WAS NORMAL AFTER THE POWER SUPPLY MODULE WAS REPLACED.