As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SLIDE LEVER WAS EXTREMELY DIFFICULT TO DISARM AFTER SHUTDOWN PRIOR TO OPENING DOOR. PERFORMED OPERATIONAL TEST OF THE MAIN DOOR SLIDE LEVER REF. AMM 25-61-21/401. OPS CHECK GOOD. NO DEFECTS NOTED. BACK PRESSURE CAUSED DUE TO GROUND AC CART WAS CONNECTED BEFORE OPENING MAIN DOOR. AIRCRAFT OK FOR SERVICE.