As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) HIGH OIL TEMP WAS OBSERVED DURING FLIGHT AT 117 DEGREES ON THE NO. 2 ENGINE . FLIGHT CREW OPTED TO RETURN TO DEPARTURE AIRPORT. ON GROUND TROUBLESHOOTING REVEALED OIL COOLER DOOR WOULD NOT OPEN. MTCE REPLACE OIL COOLER DOOR ACTUATOR AND BYPASS VALVE FOR PRECAUTION. SYSTEM FUNCTION TESTED AND RETURNED TO SERVICE.