Pacifica V6-3.8L VIN L (2005)
Power Seat Motor: Description and Operation
Lumbar Motor
The power seat system includes an electrically operated lumbar support mechanism. The power lumbar adjuster and motor are concealed beneath the seat
back trim cover and padding, where they are secured to the seat back frame.
The power lumbar adjuster mechanism includes a reversible electric motor that is secured to the inboard side of the seat back frame and is connected to
cable. The motor driven cable operates the lumbar adjuster mechanism in the center of the seat back by extending and retracting the lumbar mechanism.
This action compresses or relaxes a grid of flexible slats. The more this grid is compressed, the more the slats bow outward against the center of the seat
back padding, providing additional lumbar support.
The power lumbar motor and adjuster cannot be repaired, and is serviced only as a complete unit. If the power lumbar motor or adjuster are damaged or
faulty, the entire lumbar mechanism must be replaced.
When the lumbar switch control knob is actuated, a resistance signal is sent to the Driver Door Module via hard wired connections. The driver door
module then sends the request to the Memory Heated Seat Adjustable Pedal Module (MHSAPM) via the PCI data bus circuit. The MHSAPM is
responsible for the 12v battery feed and ground path to the power seat lumbar adjuster motor. The lumbar adjuster motor operates to move the cable and
lumbar mechanism through its travel until the switch is released, or until the travel limit of the adjuster is reached.