As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) AFTER TAKEOFF, LANDING GEAR SELECTED UP AND GEAR RETRACTED, BUT THE LEFT GEAR DOORS REMAINED OPEN. GEAR SELECTED DOWN AND LEFT GEAR REMAINED UP AND LOCKED. EMERGENCY GEAR EXTENSION CARRIED OUT. THE RONSON SEQUENCING VALVE FOR THE LEFT LANDING GEAR HAD REMAINED ENERGIZED CAUSING THE PROBLEM.