As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PDX-ON FLIGHT NUMBER 2355, LEFT HAND REAR PASSENGER DOOR WARNING CAME ON AT 5,000 FEET DURING DESCENT. CABIN PRESSURIZATION LOST AND CABIN CLIMBED TO 4,000 FEET. INSPECTED PASSENGER DOOR (AFT) PERFORMED PROXIMITY OPERATIONAL TEST 31-62-00-710-001 AND FUNCTIONAL TEST OF AFT PASSENGER DOOR. OPERATIONAL CHECK GOOD. NO PARTS REPLACED. AIRCRAFT RETURNED TO SERVICE.