As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LT HPSOV AT LOW POWER. LOCKED HIGH STG VALVE CLOSED PER MEL. FOUND PRV CONTROLLER FAILED HEALTH CHECK. REF PRESSURE VERY LOW AT ALL 5 TABLE LIMITS. REPLACED PRV CONTROLLER PER MM. ACP PNEUMATIC HEALTH CK OF HPSOV, PRV AND FAV SYSTEM WITH LEAK CHECK OF LINES. ALL SYSTEMS CHECKED GOOD AFTER PRV CONTROLLER REPLACED. BLEED OPS CHECK DURING ENG RUN CHECKS GOOD.