As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE NOSE LANDING GEAR RED UNSAFE LIGHT REMAINED ILLUMINATED AFTER GEAR RETRACTION. CHECKLIST PROCEDURES WERE COMPLIED WITH AND THE AIRCRAFT WAS RETURNED. MAINTENANCE FOUND THE NOSE GEAR DOWNLOCK SENSOR AT FAULT. THE DOWNLOCK SENSOR WAS REMOVED AND REPLACED. THE NOSE GEAR WAS CYCLED SEVERAL TIMES WITH OPERATION AND INDICATIONS CHECKING GOOD PER MM 32-60-00.