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Lumbar Support Description and Operation

LUMBAR SUPPORT SYSTEM COMPONENTS
The lumbar support system for the driver and passenger seat consists of the following components:
^ Lumbar/bolster switch
^ Seat lumbar motor
^ Seat bolster motor
^ SEAT 25A circuit breaker

LUMBAR SUPPORT SYSTEM OPERATION
The lumbar support and bolster motors are operated by a four position switch in each seat. Battery voltage is supplied to the lumbar/bolster switch from the SEAT 25A circuit breaker. While the lumbar/bolster switches are in an inactive state the switch contacts are closed to the lumbar/bolster switch ground circuit. When a lumbar/bolster switch is pressed to an active state the switch contact is closed to the battery voltage supply circuit. Each lumbar/bolster motor is controlled by the lumbar/bolster switch through 2 motor control circuits. The lumbar/bolster motors are bidirectional and the direction of motor rotation is determined by which of the motor control circuits is switched to battery voltage while the other remains grounded.