As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PRIOR TO BOARDING, FLIGHT ATTENDANT REPORTED THAT AFT LEFT SERVICE DOOR WAS VERY DIFFICULT TO OPEN. MAINTENANCE ACCOMPLISHED TEST IAW MM 52-13-00, REPLACED THE GUIDE ARM IAW MM 52-41-00 AND SNUBBER IAW MM 52-13-51 AND PERFORMED SATISFACTORY OPERATIONAL CHECK. AIRCRAFT WAS GROUNDED.