As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PEDALS WERE STIFF WITH NO RESISTANCE AND PLANE WAS NOT SLOWING. UPON EMERGENCY BRAKE APPLICATION, THE BRAKE PEDALS REENGAGED. FOUND AIR IN BRAKE SYSTEM. PERFORMED BRAKE BLEED AND EMERGENCY SYSTEM PURGE IAW MM 32-40-00-201. SERVICED EMERGENCY BRAKE NITROGEN IAW MM 12-10-00. RESET AND SAFETIED EMERGENCY BRAKE CONTROL. TAXIED ACFT. BRAKES OPS CHECKED GOOD.