As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHILE CLOSING MAIN DOOR, I HEARD A POP AND THE DOOR FELL OUT OF MY HAND AND SLAMMED DOWN. THE PULLEY INSIDE THE DOOR IS BROKEN. PHOTO WAS TAKEN WITH THE DOOR SLIGHTLY LIFTED UP. REMOVED AND REPLACED CABIN DOOR COUNTERBALANCE SPRING WITH NEW. IAW MM 52-10-50.