As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
MKE FLT2000 THE CREW REPORTED A HYDRAULIC SYSTEM NR 2 FAIL MESSAGE IN FLIGHT. THE AIRCRAFT DIVERTED INTO CLE AND LANDED WITHOUT INCIDENT. MAINTENANCE INSPECTED AND REPLACED THE O-RING ON THE NR 2 HYDRAULIC SYSTEM PRESSURE TRANSDUCER/TRANSMITTER. OPERATIONAL CHECKS WERE GOOD.