The memory seat system consists of the memory seat module (MSM), 5 seat motors, and 2 lumbar motors. The MSM controls the movement of the 5 seat position motors and the 2 lumbar motors. All of the motors operate independently of each other. Each motor contains an electronic circuit breaker (PTC), which will reset only after voltage has been removed from the motor.

There are 3 motors that move the position of the seat. These are the horizontal, front vertical, and rear vertical motors. The horizontal motor moves the entire seat forward and backward. When selected independently, the vertical motors will tilt either the front or rear of the seat up or down. Both vertical motors run simultaneously when the seat switch is operated in order to move the entire seat up or down. The recline motor moves the angle of the seatback forward or backward and the headrest motor moves the height of the headrest.

All motors are reversible. For example, the seat is moved forward and backward by one motor. When the MSM receives a signal to move the seat forward, the MSM supplies battery positive voltage (B+) and ground to run the motor in order to move the seat forward. When the MSM receives a seat backward signal, the MSM still supplies power to the same motor, except that battery voltage and ground will be applied on the opposite motor cavities. The voltage polarity is reversed and the motor will run the opposite direction moving the seat backward. The other seat motors are also powered this way.

The MSM provides each seat motor with a soft stop. The module will actually stop the motor just before the physical end-of-travel for that seat function. This decreases the stress on the motor. If a motor reaches the end-of-travel due a soft stop and the seat switch is released, then activated again, the seat will move a short distance farther to the physical travel limit.

The position sensors are potentiometers which are either attached directly to the motor or to the transmission cable attached to it. When the cable or motor rotates, the resistance of the potentiometer varies the feedback voltage monitored by the MSM to determine the seat's position. The sensor feedback voltage varies from 0.5 volts to 4.5 volts. When a memory set command is received, the MSM records the seat position by storing the feedback voltage from each position sensor. When a memory recall command is received, the MSM moves the motors until all the position sensor feedback voltages equal the feedback voltages stored in memory. For easy exit functions, only seat position sensor feedback voltages are recorded and only the seat motors are controlled. The lumbar support is not involved in the easy exit function.

The memory seat module (MSM) receives the seat and lumbar manual movement inputs from the seat switch. When a horizontal, rear vertical, front vertical, recline, headrest, or lumbar signal is received, the MSM supplies battery positive voltage (B+) and ground to the appropriate motor(s) and the seat, seatback, headrest, or lumbar move accordingly.

The driver's door switch assembly (DDSA) receives the inputs from the memory function switch. The DDSA then sends a message via the serial data class 2 line to the driver door module (DDM) indicating that memory function input has been received. The DDM then sends a message to the memory seat module (MSM) via class 2 serial data line. The current position may be recorded for 2 different drivers. To record the current position, the SET button is pressed followed by the 1 or 2 button, which is followed by a beep to acknowledge the input. When the MSM receives a memory set message, the MSM records the feedback voltages from the position sensors for the appropriate driver. To record an easy exit position, the SET button is pressed followed by the EXIT button and the 1 or 2 button, which is followed by a beep to acknowledge the input. When the MSM receives a set easy exit message, the MSM records the feedback voltages from the three seat position sensors and the recline position sensor for the appropriate driver.

When the 1 or 2 button is pressed, a single beep is sounded in order to acknowledge the input and the MSM receives the memory recall message. The MSM then applies battery positive voltage (B+) to the motors until the position sensor feedback voltages equal the feedback voltages stored in memory for the appropriate driver. When the EXIT button is pressed, a single beep is sounded in order to acknowledge the input and the MSM receives the easy exit message. The MSM then applies battery positive voltage (B+) to the seat motors until the position sensor feedback voltages equal the feedback voltages stored in memory for the appropriate driver easy exit.

When a keyless entry transmitter is used in order to unlock the vehicle's doors, the remote keyless entry (RKE) module communicates the unlock command and which driver performed the command to the MSM via a class 2 message. There are 3 personalized recall options when the MSM receives an unlock message:

The memory seat module (MSM) receives the ignition switch input and the gear selector position via class 2 messages. When the ignition switch is in the OFF position, memory record, memory recall, personalization recall, and exit recall functions are all allowed. When the ignition switch is in the ON position and the gear selector is in the PARK position, only the recall personalization function is deactivated and all other memory functions are allowed. When the ignition switch is in the ON position and the gear selector is out of the PARK position, memory record is allowed, but all other memory seat functions are not allowed.