Circuit Description

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The seat adjuster motors are controlled by the memory seat module through the adjuster motor control circuits. In an inactive state both of the motor control circuits are grounded within the memory seat module. In an active state the memory seat module switches the appropriate motor control circuit to battery positive voltage. The direction of the adjuster motor rotation is determined by which of the motor control circuits is switched to battery positive voltage while the other remains grounded. During adjuster motor operation the memory seat module also monitors the current flow through the motor control circuits.

The memory seat module monitors the positions of the horizontal, front vertical, and rear vertical adjuster motors using 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 then monitored within the memory seat module. During adjuster motor operation the hall effect position sensor provides a single pulse for every adjuster motor shaft rotation. 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.