The heated seats consist of the following components:

The driver and passenger heated seats are controlled by separate heated seat switches. Both switches are located in the integrated center stack (ICS). When a heated seat switch is pressed, a message is sent via the CAN graphical interface (CGI) serial data line to the radio. The radio then serves as a gateway to transmit the message to the memory seat module (MSM) via GMLAN serial data indicating the heated seat command. In response to this signal, the MSM then applies or removes battery voltage through the element supply voltage circuit of the seat heating elements. The MSM then sends a serial data message back to the radio to gateway the information to the ICS to either illuminate or turn off the appropriate temperature indicator.

The heated seat system is designed to warm the seat cushion and seat back to approximately 42°C (107.6°F) when in the high position, 39.5°C (103°F) when in the MED position, and 37°C (98.6°F) when in the low position. The memory seat module (MSM) monitors the seat temperature through the temperature sensor signal circuits and the temperature sensors (thermistor) that are located in the seat cushion and the seat back. The temperature sensors are variable resistors, their resistance varies as the temperature of the seat changes. When the temperature sensor resistance indicates to the MSM that the seat has reached the desired temperature, the module opens the ground path of the seat heating elements through the heated seat element control circuit. The module will then cycle the element control circuit open and closed in order to maintain the desired temperature.

The vented seat operation is designed to draw cabin air around and away from the occupant through small holes in the seat cushion and seat back covers, through channels in the foam pad, and then through the blower motor exhausting the waste air under the seat cushion.

The driver and passenger vented seats are controlled by separate vented seat switches located in the integrated center stack (ICS) with the radio and HVAC controls. With the ignition ON, Ignition voltage is supplied to the driver and passenger seat blower motors through the MISC IGN fuse located in the underdood fuse block. Ground from G200 is provided to the driver seat blower motors, while G201 provides ground for the passenger seat blower motors. When a vented seat switch is pressed, a message is sent via the CAN graphical interface (CGI) serial data line to the radio. The radio then serves as a gateway to transmit the message to the memory seat module (MSM) via the GMLAN serial data line indicating the vented seat command. In response to this message, the MSM applies a low side pulse width modulation (PWM) signal through the blower motor control circuits to the seat cushion and seat back blower motors indicating the vented seat command. The logic in the blower motors then sets the blower speed to the switch set point. Both blower motors run drawing cabin air around and away from occupant. The MSM then sends a serial data message back to the radio to gateway the information back to the ICS to either illuminate or turn off the appropriate switch indicator.

The electrical power management function is designed to monitor the vehicle electrical load and determine when the battery is potentially in a high discharge condition. The heated seat system is one of the vehicle loads that is subject to reduction during a battery discharge condition. For more information on load management refer to Electrical Power Management Description and Operation .