Operation CHARM: Car repair manuals for everyone.

Motors

There are three motors that move the position of the seat. These are the forward/back motor, rear height motor, and front height motor. Both height motors run simultaneously when the LH seat switch is operated to move the entire seat up and down. The recline motor moves the angle of the seatback. The headrest motor moves the height of the headrest.

All motors are reversible. For example, the seat is moved forward and back by one motor. When the Memory Seat Module (MSM) receives an input to move the seat forward, it supplies battery positive voltage (B+) and ground to run the motor to move the seat forward. When it receives a seat back input, the MSM will supply power to the same motor, but the voltage and ground will be on the opposite motor cavities. The voltage polarity is reversed and the motor will run the opposite direction, moving the seat back. All other seat, lumbar, and mirror motors are also powered this way.

The MSM provides each seat motor with a soft stop. The module will actually stop the motor just before the physical end-of-travel for that motor. This decreases the stress on each motor. If a motor reaches the end-of-travel due a soft stop and the seat switch is released and then -activated again, the seat will move a short distance farther, to the physical travel limit.