As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ONT INFLIGHT T1419/19MAY STL TO LAS. NUMBER ONE ENGINE CONSTANT SPEED DRIVE OIL PRESSURE LOW INDICATION DURING FLIGHT. LANDED ONT WITHOUT INCIDENT. REPLACED NUMBER ONE ENGINE CONSTANT SPEED DRIVE AND CONSTANT SPEED DRIVE AIR/OIL HEAT EXCHANGER. SYSTEM GROUND CHECKED NORMAL OPERATION. (CLOSED) (A)