As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
YIP - INBOUND TO YIP THE LANDING GEAR WAS SELECTED DOWN. INDICATION WAS 3 GREEN LIGHTS WITH A GEAR DOOR UNSAFE LIGHT. THE LANDING GEAR WAS RECYCLED AND THE GEAR DOOR UNSAFE LIGHT WENT OUT. THE AIRCRAFT LANDED AT ITS INTENDED DESTINATION AT YIP. CHECKED AND ADJUSTED THE LEFT GEAR DOOR POSITION SWITCH. OPS CHECKS OK. WORK PERFORMED IAW DC9 MM CHAPTER 32-60-3. (M)