As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
R GEN DRIVE LIGHT ILLUMINTAED DURING TAXI AFTER START R ENGINE CA-BIT GCU. GCU FAULTS IDG FOR SERVICING. SERVICED RT IDG PER AMM. RESET GCU. RAN ENGINE LOADED RT IDG HELD ENTIRE LOAD FOR 6 MIN. TRANSFER POWER ALL CHECKS OK. EXAMINED IDG FOR LEAK. NO DEFECTS WITNESSED ACFT OK FOR SERVICE ETOPS CATEGORY 'E': PROBLEMS WITH SYSTEMS CRITICAL TO ETOPS