TL* THE CONTACT OWNS A 2002 SUBARU IMPREZA. AFTER ADJUSTING THE REAR OF THE DRIVER'S SEAT, THE BACK OF THE SEAT SUDDENLY RELEASED AND CAUSED THE OCCUPANT TO FALL BACKWARDS WHILE IN THE SEAT. DURING THE INCIDENT, THE OCCUPANT SUSTAINED A CONCUSSION. MEDICAL ATTENTION WAS RECEIVED. THE CAUSE OF THE FAILURE WAS NOT DIAGNOSED OR REPAIRED. THE MANUFACTURER WAS NOTIFIED. THE FAILURE MILEAGE WAS 105,000.