As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ASH FLT 7304 IAD-JAX. CAPTAIN DECLARED AN EMERGENCY AND DIVERTED TO RDU DUE TO LOW OIL PRESSURE MASTER WARNING IN FLIGHT. MX FOUND OIL ON CONNECTOR FOR PRESSURE SWITCH, CLEANED AND RE-SECURED. PERFORMED ENGINE RUNS, OIL TEMP AND OIL PRESSURES NORMAL.