As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) AIR TURNBACK DUE TO PASSENGER DOOR WARNING AND PAX DOOR STOW CAUTION MSG POSTED. AT 1,500 FT AGL PASSENGER DOOR UNSAFE CAUTION MESSAGE CAME ON. AT 10,000 FT RED PASSENGER DOOR WARNING MESSAGE WAS POSTED. RETURNED TO AIRPORT. INSPECTED PASSENGER DOOR FOR LOOSE OR DAMAGED PARTS. REPLACED OUTER HANDLE AND CLEANED INNER HANDLE DETENT ROLLER. PRESSURIZED TO APPROXIMATELY 6 PSI. OPS AND LEAK CHECKED GOOD.