As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING FLAP RETRACTION ON CLIMB, THE CREW RECEIVED A HYDRAULIC SYSTEM 1 LOW PRESSURE CAUTION MESSAGE. THE AIRCRAFT RETURNED TO FIELD AND LANDED WITHOUT INCIDENT. FOUND ENGINE DRIVEN PUMP 1 SUPPLY QUICK DISCONNECT AT THE LINE DISCONNECTED. MAINTENANCE RECONNECTED THE LINE AND PERFORMED CHECKS IAW AMM. OPS CHECKED GOOD, THE AIRCRAFT WAS RELEASED FOR SERVICE.