As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
INBOUND CREW REPORTS LOUD SQUEAL FROM L-1 DOOR. A F/A REPORTS L-1 DOOR VERY HARD TO CLOSE. GROUNDED - YES. OPERATED L-1 DOOR SEVERAL TIMES INSIDE AND OUT, THEN HAD F/A AND CAPT OPERATE, ALL CONCUR DOOR CLOSES NORMALLY. INSPECTED LUGS AND SEALS, NO DISCREPANCIES. PRESSURIZED A/C TO 2.5 DIFF PRESS, NO ABNORMALITIES OR SQUEAL.