As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
EN ROUTE FROM FAT TO SFO, DUCT LEAK LIGHT FOR LEFT ENGINE CAME ON. LIGHT STAYED ON FOLLOWING QRH PROCEDURES. SHUT DOWN LEFT ENGINE AND MADE AN DIVERTED TO MOD. LEFT PRESSURE REGULATOR FOUND BAD, ALONG WITH TWO BAD SENSORS. DUCT SENSORS REPLACED. REMOVED AND REPLACED LEFT PRESSURE REGULATOR. RAN ENGINE AT POWER FOR SEVERAL MINUTES. PERFORMED TEST FLIGHT. NO DUCT LEAKS. OPS CHECKS GOOD.