Seat Temperature Control Module: Description and Operation
MODULE-HEATED SEATSDESCRIPTION
The heated seat module (3) is located under the right front seat (1). It has a single electrical connector (2) and four locking tabs that secure it to the mounting bracket (4). The module can be accessed from under the front right seat with the seat in the full back position. The mounting bracket (4) is bolted to the seat frame assembly (5)
The heated seat module is a microprocessor designed to use Controller Area Network (CAN) data bus messages from the instrument cluster also known as the Cabin Compartment Node (CCN). The CCN receives inputs from the heated seat switches and in turn signals the heated seat module to operate the heated seat elements for both front seats.
OPERATION
The heated seat module (HSM) is fed by a B+ circuit and continues to receive power regardless of ignition key position. The module is grounded to the body at all times through the electrical connector. The HSM monitors the ignition status message on the Controller Area Network (CAN) data bus. If the ignition state is ON/RUN then the HSM will power the heating elements. The heated seat system will turn Off automatically whenever the ignition switch is turned to any position except ON/RUN. In response to the CAN inputs the heated seat module will control the battery current to the appropriate heated seat elements.
When a heated seat switch CAN data bus signal is received by the heated seat module, the module energizes the selected heated seat element. If the heated seat module detects a heated seat element OPEN or SHORT circuit, it will record and store the appropriate diagnostic trouble code (DTC).