Power Seat Systems

POWER SEAT SYSTEMS

POWER SEAT - DRIVER
The memory power seat provides the driver with 2 position settings for the driver's seat. Each power seat motor is connected to the MHSAPM/MSAPM with two motor drive circuits. Each circuit is switched between battery and ground. By being able to bi-directionally drive the circuits, the MHSAPM/MSAPM controls the movement of the motors based on input from the power seat switch or from the position sensors when performing a memory recall. Each motor contains a potentiometer to monitor the seat position. To monitor the position of the motor, the MHSAPM/MSAPM 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 MHSAPM/MSAPM monitors the voltage change through the sensor on a separate signal circuit.

The MHSAPM/MSAPM stores the input value of each of the four seat potentiometers in memory when the system requests a set. The driver can initiate a memory recall, using either the door mounted memory switch or the RKE transmitter (if the remote linked to memory feature is enabled via the EVIC). When initiated, the MHSAPM/ MSAPM adjusts the four seat sensors (by using the motors) to match the memorized seat position data.

For safety, the memory seat recall is disabled by the MHSAPM/MSAPM when the vehicle is out of park position or if the speed is not zero. 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 MHSAPM/ MSAPM and the corresponding seat output would be deactivated. However, if the object obstructing the seat is removed, the seat will function normally again.

POWER SEAT - PASSENGER
The passenger power seat is controlled by the MHSAPM/MSAPM through PCI BUS messages sent from the PDM. However, there are no memory features with the passenger seat.