Circuit/System Description
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The memory seat module (MSM) controls the driver seat, adjustable pedal, and tilt steering wheel motors via half bridges that are divided into 2 groups that are connected to separate power rails internal to the module. The MSM connects all of the motor control circuits to a common reference point whenever they are not in operation. This reference point is biased to approximately 2.5 V. The MSM checks to see if this reference voltage is shorted to ground or battery before enabling any seat, adjustable pedal, or steering wheel motor.