As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON APPROACH, THE FLIGHT CREW SMELLED A LIGHT ODOR OF BURNING PLASTIC. ONCE ON THE GROUND, THE MECHANIC FOUND THE RETRACTABLE LANDING LIGHT TO BE THE SOURCE. THE SYSTEM WAS DEACTIVATED AND DEFERRED. THE AIRCRAFT WAS THEN RETURNED TO SERVICE WITH NO OTHER DEFECTS NOTED.