As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
BOS INFLIGHT T1937/01APR - LEFT ENGINE OIL FILTER MESSAGE. RETURNED TO BOS AND LANDED WITHOUT INCIDENT. FOUND CHAFED WIRE. REPLACED OIL PRESSURE SWITCH AND REPAIRED RELATED WIRE. ACCOMPLISHED OVERWEIGHT LANDING INSPECTION. SYSTEM GROUND CHECKED NORMAL OPERATION.