As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
"CABIN DOORS" WARNING LIGHT ILLUMINATED CLIMBING THROUGH 5000'. DOORS PAGE REVEALED AFT PASSENGER DOOR AJAR. PRESSURIZATION SEEMED TO BE NORMAL. RETURNED TO FIELD AND ACCOMPLISHED A UNEVENTFUL LANDING. INSPECTED AFT PASSENGER DOOR HANDLES, ALL ARE FLUSH WITH DOOR. INSPECTED PROX SENSORS AND FOUND ICE ON DOOR PROX. CLEANED AND LUBED AND REMOVED ICE. SENSOR OPS CK GOOD. ACFT OK FOR CONTINUED SERVICE. NO PARTS REPLACED.