As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON LANDING INTO ABE DURING GEAR EXTENSION LEFT MAIN GEAR UNSAFE LIGHT CAME ON WITH NO GREEN DOWN AND LOCK LIGHT ON. WENT THROUGH CHECK LIST AND LANDED. REPLACED LEFT GEAR DOWN LOCK PROXIMITY SENSOR IAW DC9 MM 32-60-01. OPERATIONAL CHECK NORMAL.