As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: ESCAPE SLIDE LT/EPSU(11WL)EXT L FAULT DISPLAYED DURING EMERGENCY POWER SUPPLY UNIT SYSTEM TEST. MAINTENANCE FOUND A LOOSE CONNECTOR ON SLIDE 3L, SECURED CONNECTOR IAND ACCOMPLISHED A SATISFACTORY OPERATIONAL CHECK WITH NO FAULTS NOTED PER AMM 25-62-47.