As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
RETURNED TO FIELD DUE TO A YELLOW HYDRAULIC LOW LEVEL INDICATION. FOUND TOP CENTER PLUG OF YELLOW SYSTEM LEAKAGE MEASUREMENT VALVE BLOWN OUT. REPLACED GROUND LEAKAGE-MEASUREMENT MANIFOLD OF THE YELLOW SYSTEM, SERVICE YELLOW SYSTEM TO FULL.