As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING LL2 WALKAROUND, FOUND EVIDENCE OF OIL LEAKAGE IN C DUCT AFT OF IDG OIL COOLER, NO NR 1 ENGINE IDG OIL LEVEL WAS BELOW REFILL LINE BUT STILL ON SIGHT GLASS. ACFT GROUNDED. REPLACED NR 1 ENGINE IDG OIL COOLER IAW AMM 24-11-21. LEAK CK GOOD.