As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER STARTING ENGINES DURING TAXI R OIL FILTER MSG CAME UP A/C RETURNED TO THE GATE AND MTX GROUNDED A/C . MTX REPLACED R ENG SCAVENGE FILTER ELEMENT AND DIFFERENTIAL PRESSURE SWITCH IAW AMM 79-21-04 + 79-35-01 LEAK + OPS CHECK GOOD ACFT REMAINS ETOPS 180. RETURNED TO SERVICE.