As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: FAULT MESSAGE FOR ESCAPE SLIDE LEFT / EMERGENCY POWER SUPPLY UNIT 13WL DISPLAYED DURING SYSTEM TEST. MAINTENANCE REPLACED THE L4 DOOR SLIDE / RAFT ASSEMBLY AND ACCOMPLISHED A SATISFACTORY OPERATIONAL TEST PER TASK CARD 26L00025011 WITH NO FAULTS NOTED.