As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT 3073 - AFTER DEPARTURE, CREW CYCLED LANDING GEAR TWICE AND IT WOULD NOT RETRACT. AIRCRAFT RETURNED TO DTW. MAINTENANCE FOUND LANDING GEAR DOOR SEQUENCE VALVE LEAKING, REPLACED O-RING ON BOTTOM INBOARD FITTING. ALL CHECKS GOOD. WORK DONE IAW DHC8MM 32-10-51.