As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) WHILE IN CRUISE FLIGHT, ENROUTE TO AN OFFSHORE PLATFORM, THE NR 2 ENGINE OIL BYPASS CAUTION LIGHT CAME ON. EMERGENCY CHECKLIST ACTIONS WERE CARRIED OUT AND THE ACFT RETURNED TO DEPARTURE WITHOUT FURTHER ISSUE. TROUBLESHOOTING DETERMINED THE BYPASS SWITCH WAS FAULTY. IT WAS REPLACED AND THE ACFT RETURNED TO SERVICE FOLLOWING POST INSTALLATION CHECKS.