As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING THE LANDING GEAR EXTENSION THE LANDING GEAR NOSE DOOR REMAINED OPEN WITH AN AMBER INDICATION ON THE MAIN PANEL. CHECKING THE ALTERNATE GEAR LIGHTS, THE NOSE GEAR WAS NOT INDICATING DOWN AND GREEN. WE RAN THE LG ALT EXT. CHECKLIST 10.14. WE TAXIED UNDER OWN POWER TO THE GATE. REMOVED FROM SERVICE. REPLACEMENT OF FAILED NGLK2 SENSOR, OTHER TROUBLESHOOTING AND GEAR OPS CHECKS. OPS CHECKS GOOD. AIRCRAFT RETURNED TO SERVICE.