As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER TAKEOFF, WHEN THE LANDING GEAR WAS BEING RAISED, WE GOT A GEAR DISAGREE AND A NOSE DOOR OPEN WARNING MESSAGES. RAN BOTH QRH€™S AND RETURNED TO FIELD. (FL #5452 - FILED CLOSED) REMOVED AND REPLACED NLG SENSOR HARNESS IN REFERENCE TO CRJ200 AMM 32-61-25. OPS CHECK GOOD AT THIS TIME .