Theory Of Operation

WARNING: This page is about a different car, the 2022 Chrysler Voyager and 2022 Chrysler Pacifica. However, it is still accessible from the selected car via links, so may be relevant.

The Passenger Memory Seat System is made up of:

Memory Seat Module-Passenger (MSMP)
Passenger Seat Switch
Memory Seat Switch
Horizontal Seat Motors
Vertical Seat Motors
Recliner Seat Motor (if equipped)

The Passenger Seat Switch is a Multiplex (Mux) switch which uses a set resistance level for each switch position. These resistances correspond to different voltages which is monitored by the MSMP over two separate circuits. When a voltage change is detected, the MSMP will command the appropriate Seat motor(s) to move the seat in the requested direction as long as the Passenger Seat Switch is held in that direction or its stops have been reached.

The Memory Switch is a Mux switch that is used to set and recall the seat positions. When a Memory Switch button is pressed, the Passenger Door Module (DDM) detects a voltage change and sends a request over the Controller Area Network (CAN) bus circuit to the MSMP to perform the requested command. If the SET button on the Memory Switch is pressed, followed by the 1 or 2 button, the MSMP will store the seat position based on the position inputs received from the hall-effect position sensors. If the 1 or 2 button on the Memory Switch is pressed, the MSMP will recall the stored seat position for that particular selection and return the seat to the stored position. Memory position may also be recalled using a linked FOBIK transmitter. For driver safety, the MSMP will prevent the memory recall function from being initiated if the transmission gear selector lever is not in the Park position or if the vehicle is moving.

The seat motors each contain a hall-effect position sensor. The hall-effect position sensor provides feedback to the MSMP in relation to the motor's position. The various motor stop positions are stored in the MSMP during initial module programming.

For further information. Refer to MODULE, MEMORY SEAT (MSM), DESCRIPTION AND OPERATION .