As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
EICAS MSG L GEN DRIVE DISPLAYED. GEN DRIVE LGT ILLUM. GENERATOR DRIVE DISCONNECTED. FOUND OIL COMING FROM IDG FUEL OIL HEAT EXCHANGER. REPLACED FUEL-OIL COOLER & FUEL-OIL COOLER BYPASS VALVE ASSEMBLY PER MM79-21-01. VERIFICATION FLT CONFIRMS NORMAL OPERATION OF THE SUBJECT SYSTEM. AC OK FOR SERVICE.