As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
A RED GEAR UNSAFE LIGHT REMAINED ILLUMINATED UPON GEAR RETRACTION AFTER TAKEOFF. THE GEAR WAS CYCLED WITH NO CHANGE. THE AIRCRAFT WAS RETURNED TO EWR. MAINTENANCE SERVICED THE NOSE GEAR SHOCK STRUT WITH NITROGEN PER EC 3200-01200 AND A DIP WAS ISSUED TO PERFORM A FULL SERVICE PER MM 32-21-02 AT THE FIRST OVERNIGHT STATION WITH MAINTENANCE CAPABILITY.