As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) DURING CRUISE FLIGHT THE PILOT NOTICED THE #1 ENGINE OIL PRESSURE READING ZERO, NO CAUTION LIGHT ILLUMINATION AND ALL OTHER PARAMETERS READING NORMAL. AIRCRAFT RETURNED TO BASE. POST FLIGHT INVESTIGATION FOUND THE OIL PRESSURE TRANSDUCER TO BE FAULTY. THE OIL PRESSURE TRANSDUCER WAS REPLACED AND GROUND RUN SERVICEABLE.