Lumbar Support Description and Operation (w/o A45, Memory Seat): Vertical

When the lumbar switch is operated to move the lumbar up, battery positive voltage (B+) is applied through the lumbar up switch contacts and the lumbar motor up control circuit to the lumbar vertical motor.

The motor is grounded through the lumbar down switch contacts and the lumbar motor down control circuit to the vertical motor. The motor runs to drive the lumbar up until the switch is released. Moving the lumbar down works similarly to moving the lumbar up, except that battery positive voltage (B+) and ground are applied on opposite circuits causing the motor to run in the opposite direction.