As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) AC LANDED AT INTENDED AIRSTRIP. PARKING BRAKE WAS SET AND ENGINES SHUTDOWN. WHEN AC WENT TO DEPART THE PARKING BRAKE WAS RELEASED BUT THE BRAKES STAYED ON. IT WAS FOUND THAT THE BRAKE CONTROL VALVE FAILED INTERNALLY, THE PLUNGER ACUTATOR SHAFT SHEARED TRAPPING THE BRAKE FLUID IN THE LINES TO THE BRAKES. A MAINTENANCE CREW WAS SENT TO REPLACE THE CONTROL VALVE AND THE AIRCRAFT CONTINUED ON ITS WAY.