As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER LANDING THE CREW REPORTED THE BRAKES WERE MUSHY AND COULD ONLY ACHIEVE 200-300 PSI WITH BRAKES FULLY DEPRESSED. THE CREW WAS ABLE TO PUMP THE BRAKES UP AFTER ENGINE SHUT DOWN. MAINTENANCE GAINED ACCESS TO THE BRAKE CONTROL VALVE AND BLED THE PILOT AND COPILOT MASTER CYLINDERS. MX DID FIND AIR IN THE SYSTEM. THEY PERFORMED A GOOD OPS AND TAXI CHECK.