GM Service Manual Online
For 1990-2009 cars only

Memory Seat System Components

The memory seat system consists of the following components:

    • The seat adjuster switch
    • The LH door switch
    • The memory seat module
    • The horizontal adjuster motor
    • The front vertical adjuster motor
    • The rear vertical adjuster motor
    • The SCM-L 10A fuse
    • The PWR ST/DRV 20A circuit breaker

Memory Seat System Controls

The memory seat system is controlled by the following components:

    • The seat adjuster switch
    • The memory seat module
    • The body control module
    • The LH door control module

Memory Seat System Operation

The seat adjuster motors are controlled by the memory seat module through the adjuster motor supply circuits. In an inactive state the adjuster motor supply circuits are grounded through switch contacts within the memory seat module. Adjuster motor operation occurs when the memory seat module switches one of the adjuster motor supply circuits to battery positive voltage. The direction of the adjuster motor rotation is determined by which of the adjuster motor supply circuits is switched to battery positive voltage and which remains grounded.

The seat adjuster switch signal circuits are supplied with 12 volts through resistors within the memory seat module. When a seat adjuster switch is pressed the signal circuit is grounded. Closing the signal circuit to ground pulls the voltage low indicating to the memory seat module the switch status is active. The memory seat module also relies on messages received through the serial data circuit from other control modules to perform some memory seat functions.

The seat adjuster motors are equipped with position sensors. The position sensors are supplied with a 5 volt reference circuit and low reference circuit from the memory seat module. Whenever a memory seat module function is active the memory seat module receives a signal from each position sensor which varies from 0 to 5 volts depending on the seat position. The memory seat module uses the position sensor signal voltages to determine the seat position when storing or recalling seat position settings.