As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON DEPARTURE WITH PARKING BRAKE RELEASED AND APPLICATION OF POWER, AIRCRAFT WOULD NOT MOVE. REMOVED FROM SERVICE. REMOVED AND REPLACED PARK BRAKE CONTROL VALVE REF TASK 32-44-01-000-801 AND 32-44-01-400-801. OPS AND LEAK CHECKS GOOD. BRAKES RELEASED OK ON TAXI CHECK. AIRCRAFT RETURNED TO SERVICE.