As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: REF MIC 7196981 SOF EVENT. MAINTENANCE FOUND EVIDENCE OF DRY HYDRAULIC FLUID IN AND AROUND THE APUPLENUM AND BULK HEAD SEAL AND THE COOLING FAN. FOUND APU GEN DRAIN PLUG LEAKING. REMOVED AND REPLACED APU GEN DRAIN PLUG O-RING IAW AMM 24-23-51.