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Lumbar Support Adjustment, Basic Function - GF91.00-P-9902A

Model All (CAR) with code U22 (Lumbar support adjustment) 

G15379744Courtesy of MERCEDES-BENZ USA

Overview: 

This document contains information on:

General 

To achieve optimum support of the vertebral column, the backrests on the driver and front passenger seat are each equipped with a lumbar support unit. This adjusts the shape of the seat backrest padding with the aid of two air cushions in the backrest.

Function requirements 

Manual adjustment function 

Adjustment is performed via the lumbar support adjustment switch of the respective seat. The lumbar support adjustment control unit of the respective seat reads in the status of the lumbar support adjustment switch. Then it actuates the corresponding inflation or deflation of the air cushions via the valves integrated in the control unit. For compressed-air supply, the lumbar support adjustment control unit actuates the lumbar support pneumatic pump.

IMPORTANT After switching off circuit 15R, adjustment of the lumbar support is still possible for another 180s (run-on time). If, during the run-on time, the circuits status or the door status is changed, the run-on time starts again.