As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON LEVEL OFF AT FL 370 RT BLEED OFF LIGHT ILLUMINATED LIGHT WENT OUT WHEN RESET PER QRH. L BLEED DUCT PRESSURE 40 PSI. RT BLEED DUCT PRESSURE 20 PSI. RT BLEED TRIP OFF LIGHT ILLUMINATED AGAIN LEAVING FL 370 WITH THROTTLES AT IDLE LIGHT RESET PER QRH AND BOTH DUCT PRESSURE READ APPROX 20 PSI DURING DESCENT. REMOVED AND REPLACED PRECOOLER CONTROL VALVE IN REF MM 36 12 02. PERFORMED REPAIR CONFIRMATION IN REF MM FAULT ISOLATION MM 36 10 00 810 801.