Lumbar Support System

The lumbar support system consists of:

• Seat back control switch and housing (14C715)/one-way check valve.
• Lumbar support air bag.
• Front seat back pad adjusting pump (65530).
• Front seat adjusting motor drive tube (618B62).
• System wiring and circuit protection.

The lumber support system operates as follows:

• During the inflate mode, the front seat back pad adjusting pump pumps air through a front seat adjusting motor drive tube to the lumbar switch check valve. The check valve then routes the air through a separate front seat adjusting motor drive tube to the front seat back pad adjuster (65500) .
• The front seat back pad adjuster is located at the front seat back.
• Other system components are located at or under the front seat cushion frame and spring (63100) .

The seat back control switch and housing performs three functions:

• Turns motor on which turns front seat back pad adjusting pump on.
• Acts as a one-way check valve for air passage to front seat back pad adjuster . Once inflated, the seat back control switch and housing is returned to its normal mode and the check valve closes. This maintains air pressure in the front seat back pad adjuster .
• When deflated, the check valve opens to deflate the front seat back pad adjuster . In this mode, the front seat back pad adjusting pump does not operate.

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