As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
VIBRATION EVIDENT WITH CHANGES IN AIRSPEED, PRESSURIZATION AND GEAR RETRACTION. TROUBLESHOT SYS WITH TECH REP AND FOUND BRAKE RESERVOIR PRESSURIZATION CHECK VALVE VIBRATING DURING OPERATION. CHANGED CHECK VALVE AND RELIEF VALVE THEN PRESSURIZED CABIN. NO FAULTS NOTED. OPS CHECK FLIGHT PERFORMED AND ALL SYS CHECKED GOOD.