As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING THE EMERGENCY LIGHT CHECK AS A PART OF AN OVERNIGHT LINE CHECK, THE ESCAPE SLIDE ILLUMINATION LIGHT AT DOOR 3L FAILED. MAINTENANCE REPLACED BATTERY PACK POWER SUPPLY M735, ALL OPERATIONS WERE NORMAL AFTER REPLACEMENT OF THE BATTERY PACK. (K)