As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ORD - EICAS MESSAGE RIGHT HYDRAULIC QUANTITY WITH RESERVOIR LIGHT ILLUMINATED. FLIGHT CONTROLS WERE NORMAL UNTIL APPROACH WHEN CONTROL PROBLEM STARTED. REINSTATED BOTH RIGHT HAND HYDRAULIC PUMPS. FLIGHT CONTROLS WERE THEN NORMAL FOR LANDING. TIGHTENED LOOSE B-NUT AT BRAKE TRANSFER VALVE. SYSTEM GROUND CHECKED NORMAL OPERATION.