As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER TAKEOFF FROM PHL UNSAFE NOSE GEAR LIGHT CAME ON, PULLED EMERGENCY BOTTLE AS PER EMERGENCY CHECKLIST. REPLACED 2 DEFECTIVE BULBS AT NOSE GEAR DOWNLOCK INDICATOR WITH 2 NEW BULBS. RESET GEAR DOWNLOCK VALVE AND SAFETIED, COMPLIED WITH GEAR RETRACTION CHECKS / FUNCTION CHECKS IAW CESSNA 560XL MM CHAPTER 32-61-00.