As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LEFT DUCT LEAKAGE LIGHT ILLUMINATED DURING FLIGHT. FOLLOWED QRH BUT LIGHT DID NOT EXTINGUISH AFTER 3 MIN. PERFORMED PRECAUTIONARY ENGINE SHUT DOWN AND RETURNED TO PSP. REPLACED LEFT WATER SEPARATOR. RAN LEFT ENGINE WITH POWER, CHECKS GOOD.