As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PILOT REPORTED THAT THE LT BRAKE WAS INOPERATIVE FROM THE CAPTAIN SEAT, EXTREMELY SOFT FROM THE FIRST OFFICER SEAT. REPLACED O RINGS ON THE SWIVEL FITTINGS ON THE NR 1 BRAKE. REPLACED THE CAPTAINS LT MASTER CYLINDER IAW BMM 32-40-06. OPERATIONS CHECK & LEAK CHECKED GOOD.