Circuit/System Description
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The memory seat module (MSM) controls the seat, recline, lumbar, and adjustable pedal motors via half bridges that are connected to a common power rail 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 volts. The MSM checks to see if this reference voltage is shorted to ground or battery before enabling any seat, lumbar, or adjustable pedal motor.