Vehicule seat occupant sensor and heater device

A seat occupant sensor and heater device (110) configured for use in a vehicle seat (20) including an occupant detection electrode (114) and a seat heating element (122). The occupant detection electrode (114) may be configured to capacitively detect and classify a seat occupant in accordance with Federal Motor Vehicle Safety Standard FMVSS-208. The device (110) includes a compressible spacer (128) disposed intermediate to the occupant detection electrode (114) and the seat heating element (122). The compressible spacer (128) is configured to reduce capacitive coupling between the occupant detection electrode (114) and the seat heating element (122) when uncompressed and increase capacitive coupling between the occupant detection electrode (114) and the seat heating element (122) when compressed. The seat occupant sensor and heater device (210) may exclude a fabric covering on the occupant detection electrode (214) in order to improve sensitivity of the occupant detection electrode (214) in high humidity conditions, i.e. relative humidity near or above 85 percent.