Occupant classification system with seat back sensor

A classification system, for determining the occupancy state of a seat of a vehicle, the system comprising:

• a first electrode located in a back portion of the seat;
• a second electrode located in a base portion of the seat;
• a control unit configured to send a voltage signal to each of the first and second electrodes;
• a measurement circuit configured to measure a property of the voltage signals provided to the first and second electrodes;
• a controller configured to send an occupancy signal indicative of the occupancy state of the seat based on the detected change in the voltage signals, wherein the controller is configured to determine that the seat is occupied if both the measured property of the voltage signal to the first electrode and the measured property of the voltage signal to the second electrode indicate that the seat is occupied;
• and
• wherein the controller is configured to send the occupancy signal to a Seat Belt Reminder (SBR) system.