Seats: Description and Operation

CIRCUIT OPERATION

There are four reversible motors that operate the Power Seats. The front and back height of a seat are operated by different Motors. They can be raised or lowered independently of each other. When the Entire Seat Switch is pushed to the UP and DOWN position, both Motors run to move the front and back of the seat at the same time.


RH SEAT

The Forward/Back Motor is operated by the Entire Seat Switch. When it is held in the FORWARD position, battery voltage is applied through the Switch contacts to the Forward/Back Motor. The Motor is grounded through the contact of the Back Switch to ground G202. The Motor runs to drive the seat forward until the Switch is released.

In the BACK position, the polarity of the applied voltage is reversed. This reversed polarity causes the motor to run in the opposite direction and drive the seat backward.

The Front Height and Rear Height Motors work in a similar way when the Front Height or Rear Height Switch is operated.

To raise the entire seat, the Entire Seat Switch is held in the UP position. This applies battery voltage to both the Front Height and Rear Height Motors. Both Motors run to drive the entire seat up. A similar action occurs with the reverse polarity to move the entire seat down.

Each Motor contains a self-resetting Circuit Breaker to protect it from overload.


LH MEMORY SEAT


The LH Seat operates similarly to the RH Seat for the Power Seat functions, but not when the Memory Seat functions, are operated. However, the voltages from the Seat Switch Assembly are first applied to the Seat Memory Module, which then operates the Motors, depending on the Switch inputs received.

The Left Seat Memory operates by storing the voltage appearing at the motor position sensor inputs when the SET MEMORY push button is depressed.

The input voltage of each Motor Position Sensor varies from 0 to 5 volts, depending upon the location of each seat Motor. When one of the Memory buttons is pressed, the Module applies voltage to the Motors until the Sensor voltages equal the stored values. The seat will then have returned to the stored position.

The Memory Seat functions are disabled by the Memory Seat Relay. The Relay is energized by circuits in the Seat Memory Module only when seeking or setting a memory location. When energized, the Memory Seat Relay applies battery voltage to the Memory Enable Input.

When the Gear Selector Switch is in PARK the 12 volt input is removed from the Memory Button Latch Disable Input. This allows the memory circuits to move the seat to the stored position whenever a memory button is pressed With the 12 volts applied, the memory button must be held until the seat completes its movement.