As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CLIMB, CABIN BECAME UNCONTROLLABLE. DESCENDED TO 10,000 FEET AND RETURNED TO DTW AND LANDED WITHOUT INCIDENT. MAINTENANCE PERFORMED VESSEL LEAK CHECK, FOUND A NUMBER OF AIR LEAKS FROM THE KEEL WATER DRAINS. REPAIRED AIR LEAKS AND MADE REPAIRS TO CHAFED PRESSURE LINES AND CRACKED DUCTING. PERFORMED OPERATIONAL CHECK OF PRESSURIZATION SYSTEM, SYSTEM CHECKED OK.