As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIR TURN BACK DUE TO BLUE HYDRAULIC RESERVOIR LOW INDICATION ON THE ELECTRONIC CENTRALIZED AIRCRAFT MONITORING SYSTEM. MAINTENANCE APPLIED MEL 29-30-04F FOR THE RESERVOIR LOW LEVEL SWITCH, COMPLIED WITH FOLLOW-UP ACTION TO VERIFY THE BLUE HYDRAULIC RESERVOIR LEVEL WAS ADEQUATE IAW WITH MEL REQUIREMENTS AND RETURNED THE AIRCRAFT TO SERVICE.