As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT DEPARTED FROM KHPN EN ROUTE TO KFPR. CREW SELECTED GEAR HANDLE DOWN AND RECEIVED A RED HANDLE WARNING INDICATION. AIRCRAFT FLEW PAST CONTROL TOWER TO VERIFY THE LANDING GEAR WAS DOWN. RETRACTED LANDING GEAR AND DIVERTED TO KPBI AND LANDED WITH OUT INCIDENT. AIRCRAFT WAS BROUGHT TO GENERAL DYNAMICS WHERE THE LEFT MAIN LANDING GEAR DOWN AND LOCKED SWITCH WAS REPLACED.