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GF91.25-P-0001GM Multicontour Seat (MCS), Function




GF91.25-P-0001GM Multicontour Seat (MCS), Function
- as of model year 09/YoM 08 model refinement package with CODE (409) Left/right front multicontour seat [model 164.1]
- as of model year 09/YoM 08 with CODE (409) Left/right front multicontour seat [models 164.8 and 251.1]

Function requirements, general
^ Circuit 15 or circuit 15R ON
^ No overvoltage or undervoltage
^ No damage to the compressed air supply

Function description of multicontour seat, general
The pneumatic pump for the multicontour seat (M40) receives its power from the rear SAM control unit (N10/8) via the load compartment fuse and relay box (F4).

The multicontour seat can be adjusted individually.

The individual adjustment of the contour and the surface hardness of the backrest and of the seat cushion is made possible by filling and purging.

The air cushions are located as follows:
- in the backrest area at the left and right,
- in the upper lumbar area,
- in the lower lumbar area and
- in the front upper leg area of the seat cushion.

Lumbar support = curvature of spine in lumbar region.

The filling and purging control of the individual air cushions is done manually via the:
- control valve for seat cushion fore/aft adjustment
- control valve for lower lumbar support adjustment
- cross-shaped rocker button for control valve block for the multicontour seat

located in the:
- Control valve block for multicontour seat

The multicontour seat enables the following subfunctions to be performed:
^ Adjustment of seat cushion length
^ Height adjustment of the lumbar contour
^ Adjustment of the lower lumbar support area
^ Adjustment of the upper lumbar support area
^ Adjustment of the lateral support

Adjustment of seat cushion length
The front area of the multicontour seat cushion is adjusted using the control valve for seat cushion fore/aft adjustment.

If the control valve for seat cushion fore/aft adjustment is actuated in the forward or rearward direction, the seat cushion contour in the upper leg area is changed by inflating or deflating the air cushion for the seat cushion length.

Height adjustment of the lumbar contour
If the cross-shaped rocker button of the control valve block for the multicontour seat is actuated upwards "up arrow" or downwards "down arrow" the air cushion for the lower or upper lumbar support is activated to match the request and separately inflated or deflated.
- If the cross-shaped rocker button is moved towards "up arrow" the air pressure in the air cushion for the upper lumbar support increases, and drops in the air cushion for the lower lumbar support.
- If the cross-shaped rocker button is moved towards "down arrow" the air pressure in the air cushion for the upper lumbar support drops, and increases in the air cushion for the lower lumbar support.

The supply of compressed air is distributed by the control valve block for the multicontour seat via the pneumatic lines to the air cushion for the upper lumbar support and the air cushion for the lower lumbar support to match the driver's needs.

Adjustment of the lower lumbar support area
The lower lumbar area of the multicontour backrest is adjusted using the cross-shaped rocker button of the control valve block for the multicontour seat.

If the cross-shaped rocker button of the control valve block for the multicontour seat is moved towards "+" or "-" the backrest contour in the lower lumbar area changes through inflating or deflating the currently active air cushion for the lower lumbar support.

Adjusting the upper lumbar support area
The upper lumbar area of the multicontour backrest is also adjusted using the cross-shaped rocker button of the control valve block for the multicontour seat.

If the cross-shaped rocker button of the control valve block for the multicontour seat is moved towards "+" or "-" the backrest contour in the upper lumbar area changes through inflating or deflating the currently active air cushion for the upper lumbar support.

Adjustment of the lateral support
The lateral support of the multicontour backrest is adjusted using the control valve for side bolsters adjustment.

If the control valve for side bolsters is adjusted to the left or the right, the air cushions of the left and right side bolsters of the multicontour backrest are inflated or deflated.