As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHEN CABIN ENTRANCE DOOR WAS OPENED AFTER FLIGHT, CREW NOTICED DOOR OPENED VERY RAPIDLY. INSPECTED DOOR AND FOUND FORWARD COUNTER BALANCE SPRING HAD FAILED. AFTER SPRING WAS INTACT. FORWARD COUNTER BALANCE SPRING WAS REPLACED WITH NEW. DOOR OPERATIONS CHECK GOOD.