As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SLAT DISAGREEMENT AND BLUE EXTEND LIGHTS REMAINED ON AFTER SLATS WERE RETRACTED. FLAP/SLAT HANDLE WAS DIFFICULT TO MOVE FROM ZERO TO RETRACT POSITION. FLIGHT WAS RETURNED TO DTW AND LANDED WITHOUT INCIDENT. MAINTENANCE REPLACED SLAT CONTROL VALVE. OPERATIONAL CHECK NORMAL. AIRCRAFT RETURNED TO SERVICE.