Lumbar Support (With RPO Code AM3 Without RPO Code A45)

LUMBAR SUPPORT DESCRIPTION AND OPERATION (AM3 W/O A45)

LUMBAR MASSAGE COMPONENTS
The massaging lumbar system consists of the following components:
- Lumbar Switch
- Lumbar Massage Module
- Lumbar Vertical Motor
- Lumbar Vertical Position Sensor
- PWR SEAT Circuit Breaker 30 A

POWER SUPPLY
Battery positive voltage is supplied at all times to the lumbar switch and the massage module through the battery positive circuit and the PWR SEAT Circuit Breaker located in the rear fuse block. Ground is supplied to the massage module through the module ground circuit and G 302.

LUMBAR VERTICAL MOTOR
The lumbar vertical motor is reversible. When commanded, it will move the lumbar support in the up and down directions. To protect itself, the motor contains an electronic circuit breaker (PTC) that opens in the event of a circuit overload and will reset only after voltage has been removed from the circuit. The lumbar vertical motor also contains a sensor to monitor the lumbar position during massage operation. The lumbar vertical motor is controlled by the massage module during manual movement and massage operation.

MASSAGE OPERATION
When the lumbar switch is momentarily pressed where it is marked AUTO in order to initiate the massage function, battery positive voltage is momentarily applied through the switch contacts and the lumbar motor up switch signal circuit to the massage module. In response to this signal, the massage module then cycles battery positive voltage and ground through the lumbar motor up and down control circuits to the motor. The motor will then continuously move the lumbar support 50 mm in both the up and down directions for 10 minutes or until the lumbar switch is momentarily pressed to cancel the operation. When massage operation has ceased, the massage module will return the lumbar support to the position from which massage was initiated.

During massage operation, the lumbar horizontal support can be adjusted without interruptions to the massage cycle by operating the lumbar switch in either the forward or rearward directions. However, manually moving the lumbar vertical switch in either the up or down directions will cancel the massage operation and move the lumbar support in the desired direction.

MANUAL VERTICAL MOVEMENT
When the lumbar switch is operated to move the lumbar up, battery positive voltage is applied through the lumbar up switch contacts and the lumbar motor up signal circuit to the massage module. In response to this signal, the massage module applies battery positive voltage through the lumbar motor up control circuit and ground through the lumbar motor down control circuit to the motor. The motor runs in order to drive the lumbar support up until the switch is released. When the lumbar switch is operated to move the lumbar support down, battery positive voltage is applied through the lumbar down switch contacts and the lumbar motor down switch signal circuit to the massage module. In response to this signal, the massage module applies battery positive voltage through the lumbar motor down control circuit and ground through the lumbar motor up control circuit to the motor. The motor runs to drive the lumbar support down until the switch is released.

POSITION SENSOR
The lumbar vertical position sensor is a potentiometer which is attached directly to the lumbar vertical motor. The massage module supplies a 5 volt reference voltage through the 5 volt reference circuit and ground through the low reference circuit to the lumbar vertical position sensor. When the motor rotates, the resistance of the potentiometer varies changing the feed back voltage of the position sensor signal to the massage module. This voltage varies from 0.25 volts to 4.75 volts. The massage module monitors this voltage to determine the vertical position of the lumbar support.