What was found
(CAN) AT 19,000 FEET, PASSENGER DOOR LATCH CAUTION MESSAGE CAME ON. CABIN PRESSURE NORMAL, 20 SECONDS LATER, THE PASSENGER DOOR RED WARNING CAME ON. IN DESCENT, MESSAGE CYCLED UNTIL PRESSURE WAS ZERO. SWITCHES AND BOTH SENSORS ON DOOR HANDLE WERE CLEANED AND PROXIMITY SWITCH ELECTRONIC UNIT CHECKED OK. PART TC: 5,361.