Memory Seat System Components
The memory seat system consists of the following components:
• | Power seat switch assembly |
• | Memory recall switch assembly |
• | Horizontal adjuster motor |
• | Front vertical adjuster motor |
• | Rear vertical adjuster motor |
• | SEAT 25A circuit breaker |
Memory Seat System Description
Battery voltage is supplied to the memory seat module from the SEAT
25A circuit breaker. The memory seat module supplies the seat adjuster switch
assembly with a battery positive reference voltage. While the seat adjuster
switches are in an inactive state the switch contacts are closed to the adjuster
switch ground circuit. 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 memory seat module the
switch status is active. Each seat adjuster motor is controlled by the memory
seat module 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 memory seat module. The memory seat module 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 seat adjuster motors are equipped with internal position sensors.
The adjuster motor position sensors are monitored by the memory seat module
and are used to determine the seat position when storing or recalling memory
settings. The horizontal, front vertical, and rear vertical adjuster motors
use hall effect type position sensors. The hall effect position sensors are
supplied with 5-volt reference and ground circuits from the memory seat module.
The position sensor signal circuits are supplied 5 volts through a resistor
them monitored within the memory seat module. During adjuster motor operation
the hall effect position sensor provides a single pulse for every revolution
of the adjuster motor shaft. The memory seat module counts the pulses from
the position sensor signal circuits to determine the adjuster motor positions
when storing or recalling memory seat position settings. The recline adjuster
motor is equipped with a potentiometer type position sensor. The recline
motor position sensor is supplied with it's own 5-volt reference and ground
circuits from the memory seat module. The recline position sensor signal
circuit is supplied 5 volts through a resistor then monitored within the
memory seat module. The signal voltage monitored by the memory seat module
ranges from 0.39 - 4.58 volts and is determined by the wiper
location on the resistor within the recline motor position sensor. The recline
motor position sensor signal circuit voltage level is used by the memory
seat module to determine the seat recline position when storing or recalling
memory seat position settings.
The memory recall switch assembly on the driver's door provides inputs
to the memory seat module. Battery voltage is supplied to the memory recall
switch assembly from the MIR/LOCK 3A fuse. When a SET, RCL 1, or RCL 2
switch is pressed, the switch contacts close the appropriate switch signal
circuit to the battery voltage supply circuit within the memory recall switch
assembly. Battery voltage on a switch signal indicates to the memory seat
module the switch status is active.
Memory seat recall operation is allowed only with the transmission selector
lever in the PARK position while the ignition is on. The memory seat module
determines the ignition is on using the ignition voltage supply circuit from
the IGN3 10A fuse. The memory seat module relies on in input from the shift
lock control switch supply circuit in order to determine transmission selector
lever is in the PARK position.