As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) PILOT REPORTED THAT THE BRAKES WERE NOT WORKING WELL ON 1 SIDE. MAINTENANCE FOUND THAT THE COTTER PIN, HOLDING THE BOTTOM OF THE BRAKE MASTER CYLINDER ON THE PIVOT SHAFT, HAD BEEN SHEARED OFF ALLOWING THE BRAKE CYLINDER TO MOVE SIDEWAYS AND BIND. THE COTTER PIN IS AN MS24665-24, PIN EXTREMELY LIGHT DUTY. MAINTENACE FEELS IT IS NOT HEAVY ENOUGH FOR THE APPLICATION.