FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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Power Seat


The memory power seat provides the driver with 2 position settings for the left seat. Each power seat motor is connected to the MHSMM with two circuits. Each circuit is switched between battery and ground. By alternating the circuits the MHSMM controls the movement of the motors based on input from the power seat switch or through memory recall.

Each motor contains a potentiometer to monitor the seat position. To monitor the position of the motor, the MHSMM sends out a 5-volt reference on the sensor supply circuit. The sensor is grounded back to the module on a common ground circuit. Based on the position of the sensor, the MHSMM monitors the voltage change through the sensor on a separate signal circuit.

The MHSMM stores the input value of each of the four seat potentiometers in memory when the system is requested. The driver can initiate memory recall, using either the seat mounted memory switch or the RKE transmitter. When initiated, the MHSMM adjusts the four seat motors to match the memorized seat position data.

For safety, the memory seat recall is disabled by the MHSMM when the vehicle is out of park position. Any obstruction to seat movement over a 2 second delay will cause the seat to stop moving in which case a stalled motor would be detected by the MHSMM which would then flag a trouble code and the corresponding seat output would be deactivated. However, if the object obstructing the seat is removed, the seat will function normally again.