The memory seat system consists of the following components:
• | The memory seat module (MSM) |
These motors have a position sensor attached to each motor.
The MSM controls the movement of the 3 seat position motors.
The MSM controls 1 seat back recline motor. All of the motors operate
independently of each other.
In order to power the MSM, the rear compartment fuse block BATT fuse
through CKT 1840 (ORN) supplies battery positive voltage (B+). The
left underhood fuse block SEAT circuit breaker through CKT 742
(RED) provides battery positive voltage (B+) to the MSM which is used
in order to run the seat motors. The MSM grounds through CKT 850
(BLK) to G302.
Motors
The following 3 motors move the position of the seat:
• | The rear vertical motor |
• | The front vertical motor |
Both vertical motors run simultaneously when the left seat switch signals
the entire seat to move up or down. The recline motor moves the angle of the
seat back. The headrest motor moves the height of the headrest.
All of the motors are reversible. For example, 1 motor moves
the seat both forward and back. When the seat switch sends a signal to the
MSM in order to move the seat forward, the MSM supplies the following
items in order to run the motor and move the seat forward:
• | Battery positive voltage (B+) |
When the seat switch sends a signal to the MSM in order to move the
seat back, the MSM supplies power to the same motor. The voltage and the ground
apply to the opposite cavities on the motor connector. The following
events occur in order to move the seat back:
• | The voltage polarity reverses. |
• | The motor runs in the opposite direction. |
All of the following motors run in an identical manner:
• | The power lumbar motors |
The MSM provides each seat motor with a soft stop. The module stops
the motor just before the end of travel for the seat. The soft stop decreases
the stress on each motor. If the following conditions occur, the
seat moves a short distance farther to the physical travel limit:
• | The module stops the motor using a soft stop. |
• | You release the seat switch. |
• | You activate the seat switch again. |
Position Sensors
The memory seat module (MSM) uses the position sensors in order to perform
the following functions:
• | Store the motor positions. |
• | Return the motors to the stored memory positions. |
The MSM provides a 5 volt reference voltage through CKT 788
(GRY) and the reference ground through CKT 782 (BLK) to each of the
following components:
• | The seat position sensors |
• | The lumbar position sensors |
The position sensors are potentiometers mounted to the transmission
cable of each motor. When the cable rotates, the resistance of the potentiometer
varies. The MSM monitors the feedback voltage of the potentiometer
in order to determine the position of the motor. The sensor feedback
voltages vary from 0.25 volts to 4.75 volts. When
you execute a set memory command, the MSM records each position
feedback sensor in order to store the motor positions. When you
command a memory recall, the MSM moves the motors until the feedback
voltages of all of the position sensors equal the feedback voltages
stored in memory.
For the easy exit functions, the MSM records only the seat position
sensor feedback voltages. Only the seat motors run during the easy exit function.
Manual Movement
The memory seat module (MSM) receives the manual movement inputs of
the seat from the left seat switch. When the MSM receives one of the following
inputs, the MSM supplies battery positive voltage (B+) to the appropriate
motor(s) and the seat moves accordingly:
The MSM supplies battery positive voltage (B+) to the following appropriate
motors that cause seat movement:
Memory Set
The following may be recorded for 2 different drivers
In order to record the current seat positions, press and hold one of
the following buttons for 5 seconds:
When the memory mirror module (MMM) receives these inputs, the MMM records
the feedback voltages from the 4 mirror position sensors for the appropriate
driver. A chime sounds in order to acknowledge the input. A Class 2
message to the memory seat module (MSM) is also sent informing of the SET
MEMORY command. When the MSM receives a memory set message, the MSM
records the feedback voltages from the following sensors for the appropriate
driver:
• | The seat position sensor |
• | The lumbar position sensor |
An easy exit position for each driver may also be recorded. In order
to perform this function, move the seat to a comfortable exit position. Press
the SET MEMORY button, which is followed by a chime to acknowledge the
input. Within 5 seconds, the EXIT button is pressed. The MMM identifies
the driver for the last recall or set command. This identification informs
the MSM of the set exit command. The proper driver is then recorded through
a Class 2 message.
The MSM records the following feedback voltages for the appropriate
drivers:
In order to acknowledge that the position was recorded, a single chime
is sounded. For diagnosis of the memory function switch, refer to
Outside Rearview Mirror Schematics
in Doors.
Memory Recall
When the MEMORY-1 or the MEMORY-2 is pressed, the memory mirror module
(MMM) receives this input. A chime sounds. The MMM applies battery positive
voltage (B+) to the mirror motors until all of the mirror position sensor
feedback voltages equal the voltages stored in memory for the appropriate
driver.
In order to perform the memory recall function through a Class 2
message, the memory seat module (MSM) receives a command. The MSM applies
battery positive voltage (B+) to all of the seat and the lumbar motors
until the position sensor feedback voltages equal the voltages stored in
memory for the appropriate driver.
The easy exit seat position can be recalled by pressing the EXIT button.
A single chime sounds. The MMM identifies the driver for the last recall or
set command. This identification informs the MSM of the exit recall command/driver
identification through a Class 2 message.
The MSM moves the following motors until the position sensor feedback
voltages equal the voltages stored in memory for the appropriate driver:
For diagnosis of the memory function switch, refer to
Outside Rearview Mirror Schematics
in Doors.
Recall Personalization
When you use a keyless entry transmitter in order to unlock the doors
of the vehicle, the remote function actuator (RFA) module communicates the
following information to the memory seat module (MSM) through a Class 2
message:
• | The driver that performed the command |
The following 3 personalized recall options are available when
the MSM receives an unlock command:
• | Recall immediately upon receipt of the RFA message. |
• | Recall when the MSM receives a key-in message. |
• | Do not recall upon receipt of an RFA message. Recall functions
perform only from the memory switches. |
Memory Inhibit/Enable
The memory mirror module (MMM) receives the park gear and the ignition
inputs through the Class 2 messages.
When the ignition switch is OFF, the following functions are allowed:
• | The memory record function |
• | The memory recall function |
• | The personalization recall function |
• | The exit recall function |
The personalization recall function deactivates under the following
conditions:
• | The ignition switch is ON. |
• | The gear selector is in PARK. |
All of the other memory functions remain operative.
The memory record remains active under the following conditions:
• | The ignition switch is ON. |
• | The gear selector is out of PARK. |
All of the other memory functions deactivate.