As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON CONTROL CHECK SPOILER PRESSURE WAS 2850. ON TAXI OUT PRESSURE DROPPED TO 2750. C/W ABNORMAL PROCEDURES. PUMP REGAINED 2800 PSI THEN DROPPED TO 2750. FOUND AIR IN SYSTEMS BLED AND SERVICED RESERVOIR. CYCLED SEVERAL TIMES AND CHECKS NORMAL.