Lumbar Support System

The lumbar support system consists of the seat back control switch, front seat back pad adjuster, a pump and motor assembly, related wiring harness and plastic tubing.

During the inflate mode, the front seat back pad adjusting pump pumps air through a front seat back pad adjusting hose to the lumbar switch check valve.
- The air is then routed through a separate hose to the front seat back pad adjuster lumbar support located at the seat back.
- Except for the front seat back pad adjuster, all components are located at or under the front cushion pad.

The seat back control switch performs three functions.
- First, it turns the front seat back pad adjusting pump on.
- Second, it is a one-way check valve for air passage to the front seat back pad adjuster. Once the bag is inflated and the seat back control switch is left to its normal mode, the check valve closes and prevents air in the bag from leaking out.
- Third, in the deflate mode, it opens the check valve, releasing the air deflating the front seat back pad adjuster. In this mode the front seat back pad adjusting pump does not operate.

The longer nipple on the seat back control switch (located at the center of the seat regulator control switch) should always be connected to the front seat back pad adjusting hose leading to the front seat back pad adjuster. The shorter nipple on the seat back control switch connects to the air pump outlet. If this order is reversed, the front seat back pad adjuster will not hold air pressure.