As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SEA FLIGHT: RAMP TOW TEAM ADVISES THAT NLG GROUND LOCK MECHANISM WILL NOT LOCK. MAINTENANCE REMOVED AND REPLACED NLG GROUND LOCK CONTROL LATCH ASSEMBLY. NO ADJUSTMENTS TO GROUND LOCK MECHANISM MADE. PERFORMED OPERATIONAL TEST OF NLG GROUND LOCK POSITION INDICATION SYSTEM IAW Q400 AMM TASK 32-25-06-710-801. CHECKS GOOD. AIRCRAFT RETURNED TO SERVICE.