Module, Comfort Seat And Wheel (CSWM): Description
The Comfort Seat and Wheel Module (CSWM) (1) is located under the passenger front seat. It has a single electrical connector and a push pin style retainer that secures it to the seat pan. The module can be accessed from under the passenger seat with the seat in the full back and up position.
The CSWM is a Controller Area Network-Interior High Speed (CAN-IHS) bus controller providing outputs to the power seats, heated seat pads, heated steering wheel, and seat ventilating. The CSWM receives commands over the CAN-IHS bus from the Body Control Module (BCM). The seat thermistor is hardwired to the CSWM.
Heated Seats - The CSWM uses a Pulse Width Modulation (PWM) to provide power to the seat cushion and back heating elements. The temperature sensor thermistor is located in the seat cushion. The thermistor sensor feedbacks from each seat heating element to the CSWM to regulate the heater outputs to prevent any seat temperature to rise above set points. Seat heating has two selectable heat settings which are HI and LO. Depending on thermistor reading, the CSWM will start the heater output by adjusting the PWM heat level according to the calibration table.
Vented Seats - The CSWM vents the two front seats by providing variable analog voltages driving the external blowers in the seats. The seat venting has two selectable speeds for the fans. For seat venting, each press of the switch button will cause the seat to change venting modes. The CSWM will turn on the vented seats only with the engine running.
Heated Steering Wheel - The CSWM provides power to the steering wheel heating element. The heated steering wheel is standard when the vehicle is equipped with front heated seats. During normal operation, the CSWM will switch on the power for the heated wheel only if the engine is running. The heated steering wheel temperature sensor is hard-wired to the Electronic Vehicle Information Center (EVIC) switch which sends that information over a Local Interface Network (LIN) bus through the Steering Column Control Module (SCCM) to the BCM. The thermistor sensor feedbacks from the steering wheel heating element via the CAN-IHS bus to the CSWM regulating the heater output to prevent the wheel temperature to rise above the maximum threshold temperature set point.