Front Row Seats - Vehicles With Driver Seat Memory

On vehicles with driver seat memory, the Driver Seat Module (DSM) receives 2 power supplies. The permanent power supply from the Passenger Junction Box (PJB) is used to operate the adjustment motors. The switched power supply from the Rear Junction Box (RJB) is used to operate the DSM.

A switched power supply is connected from the RJB to the driver seat switchpack. The driver seat switchpack is connected to the DSM by a Local Interconnect Network (LIN) bus to control the seat adjustment. Any selection for seat adjustment generates a message which is transmitted to the DSM through the LIN bus. The DSM processes the request and operates the applicable seat adjustment motor as required using the power supplies from the PJB.

The DSM is connected to the High Speed (HS) Controller Area Network (CAN) body systems bus. This allows the DSM to monitor the position of the door mirrors and the steering column when storing and recalling seat memory settings. The signal is provided from the Driver Door Module (DDM), the Passenger Door Module (PDM) and the Body Control Module/Gateway Module (BCM/GWM) assembly respectively. The HS CAN body systems bus connection also allows both modules to relay seat memory information. In addition, to enable confirmation chimes and message displays in the Instrument Cluster (IC).

Memory settings are stored in the DSM by pressing the seat memory switch and then, within 5 seconds, 1 of the channel switches. When the memory switch is pressed the seat memory switchpack status indicator in the switch lights up. After the channel switch is pressed, the seat memory switchpack status indicator light goes off and a chime sounds to confirm that the settings have been memorized. If the ignition is ON, the message center will display a confirmation message. Any previously stored settings on the selected channel will be overwritten.

Seat memory settings are recalled by pressing the applicable channel switch.

On seats with 4-way lumbar adjustment and seat bolster adjustment, the inflate and deflate solenoid valves are operated with a rotary switch which is located on the seat switchpack. On vehicles with massage seats, power is connected to the inflate and deflate solenoid valves in the same way. When an inflate selection is made the lumbar/massage air pump is activated by a LIN bus message to the massage solenoid valve, which then operates the lumbar/massage air pump.