As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
MOUNTING BAR CAME LOOSE FROM LINING ALLOWING IT TO FLOAT LOOSE BETWEEN PISTON AND BRAKE DISK. WHEN THE ROTOR BRAKE WAS APPLIED, THE LINING COULD BE FORCED DOWN AND WEDGE BETWEEN THE DISK AND THE CALIPER AND ACT LIKE THE BRAKE WAS ON. REPLACED LININGS AND O-RINGS AND REASSEMBLED. OPS CHECKED OK.