As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) WHEN GEAR RETRACTED, LEFT MAIN GEAR DOOR OPEN WARNING ON. GEAR RECYCLED AND FAULT THE SAME. WITH GEAR DOWN, DOOR POSITION INDICATION WAS NORMAL. INSPECTION LEAD TO CLEANING OF PROXIMITY SWITCHES. SUBMITTER SUSPECTS EITHER DEBRIS OR COLD WEATHER CAUSED THE PROBLEM.