As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING PREPARATION FOR A HEAVY MAINTENANCE VISIT, LEFT EMERGENCY EXIT DOOR NUMBER 3 EMERGENCY ESCAPE SLIDE DEPLOYED INSIDE THE CABIN DURING THE PROCESS OF DEACTIVATION. THE TECHNICIAN NOTED THAT THE DEACTIVATION PIN WAS DIFFICULT TO INSERT AND WHILE MANIPULATING THE LEVER TO INSERT THE PIN, THE SLIDE BOTTLE WAS DISCHARGED AND THE SLIDE INFLATED. THE DOOR ARMING LEVER WAS CONFIRMED TO BE IN THE "DISARMED" POSITION.