As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PILOT REPORTED NO RESPONSE FROM LT BRAKE PEDAL, FOUND THAT BOTTOM LT BRAKE MASTER CYLINDER ATTACHMENT CLEVIS PIN MISSING. LOCATED CLEVIS PIN ON UPPERSIDE OF BELLY SKIN AND COTTER PIN. FOUND THAT COTTER PIN WAS BARELY BENT AND APPEARENTLY FELL OUT O F CLEVIS PIN HOLE THUS ALLOWING CLEVIS PIN TO FALL OUT OF BRAKE MASTER CYLINDER ATTACHMENT.