As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING OVERNIGHT MAINTENANCE, MECHANIC OPENED THE L1 DOOR WHILE IT WAS ARMED AND THE L1 DOOR SLIDE DEPLOYED, HOWEVER IT FAILED TO INFLATE. MAINTENANCE INSPECTED AND FOUND THE LOCKOUT PIN STILL INSTALLED. MAINTENANCE R & R THE L1 DOOR SLIDE IAW AMM AND OPS CHECKED GOOD. ACFT IS GOOD FOR SERVICE.