As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
EWR INFLIGHT T429/30JAN - GEAR UNSAFE LIGHT ILLUMINATED DURING LANDING GEAR RETRACTION. CYCLED GEAR WITH NO HELP. RETURNED TO EWR AND LANDED WITHOUT INCIDENT. REPLACED PROXIMITY SENSOR ELECTRONIC UNIT FOR NOSE LANDING GEAR. SYSTEM GROUND CHECKED NORMAL OPERATION.