As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON APPROACH TO SCH WHEN LANDING GEAR EXTENDED THREE GREEN LIGHTS CAME ON WHILE THREE RED LIGHTS STAYED LIT AND GEAR DOORS FAILED TO CLOSE. TROUBLESHOOTING MX DISCOVERED THE LANDING GEAR CONTROL SOLENOID VALVE INTERMITTANTLY STICKING IN THE OPEN POSITION WHEN COLD. THIS PROBLEM WAS DIFFICULT TO DETECT BECAUSE IT ONLY HAPPENED WHEN VALVE BECAME COLD-SOAKED IN FLT. THE NIGHT THE PROBLEM WAS DISCOVERED BY GND MX THE AIR TEMPERATURE WAS -15 F.