Circuit/System Description

The driver and passenger vented seats are controlled by separate vented seat switches located in the HVAC controls. Ignition voltage is supplied to the driver and passenger seat blower motors through a 10A fuse located in the underhood fuse block. When a vented seat switch is pressed, a serial data message is sent from the HVAC controls to the HVAC control module indicating the vented seat command. The HVAC control module serves as a gateway to transmit the message to the seat memory control module via the serial data line. In response to this message, the seat memory control module 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 causing a cooling effect to the occupant. The seat memory control module then sends a serial data message back to the HVAC control module to gateway the information back to the HVAC controls to either illuminate or turn off the appropriate switch indicator.