Memory Seat System Components
The memory seat system consists of the following components:
• | Seat front vertical motor |
• | Seat rear vertical motor |
Memory Seat System Description
Battery voltage is supplied to the driver seat module (DSM) through the power
seat circuit breaker. The DSM supplies the seat adjuster switch assembly with a battery
positive reference voltage. When a seat adjuster switch is pressed to an active state
the switch contact is closed to the reference voltage circuit. Battery voltage on
a switch signal circuit indicates to the DSM the switch status is active. Each seat
adjuster motor is controlled by the DSM through 2 motor control circuits. While
the seat adjuster motors are in an inactive state the motor control circuits are closed
to ground circuit contacts within the DSM. The DSM operates the seat adjuster motors
by switching one of a motor's control circuits to battery voltage. The seat adjuster
motors are bidirectional and the direction of adjuster motor rotation is determined
by which of the adjuster motor control circuits is switched to battery voltage while
the other remains grounded.
Memory Set/Recall Operation
The driver seat adjuster motors are equipped with internal potentiometer type
position sensors. The adjuster motor position sensors are monitored by the DSM and
are used to determine the seat position when storing or recalling memory settings.
The front vertical, rear vertical, horizontal, and recline position sensors are supplied
with common 5-volt reference and ground circuits from the DSM. The position sensor
signal circuits are supplied 5 volts through resistors then monitored within
the DSM. The signal voltages monitored by the DSM range from 0.39-4.58 volts
and are determined by the wiper locations on the resistors within the position sensors.
The position sensor signal circuit voltage levels are used by the DSM to determine
the seat position when storing or recalling memory seat position settings.
The memory switch assembly provides inputs to the DSM. Battery voltage is supplied
to the memory switch assembly from the seat module. When a memory 1, 2, or EXIT switch
is pressed, the switch contacts close the appropriate switch signal circuit to the
battery voltage supply circuit within the memory switch assembly. When the seat module
receives active switch signals from the memory switch assembly, the appropriate seat
adjuster motors are operated, as necessary, until the position sensor signal voltages
match the stored values.
Memory seat recall operation, while the ignition is ON, is allowed only with
the transmission selector lever in the PARK position. The transmission selector lever
position data is provided to the DSM by a message through the class 2
Serial Data circuit.