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Home >> Mercedes Benz >> 2021 >> Metris Van Cargo >> Repair and Diagnosis (Single Page) >> Restraints >> Restraints Control Systems >> Seats, Bunks, Restraint Systems (1 Of 4) -- 447 Chassis >> Basic Knowledge >> Massage Function Control Unit, Basic Function - GF91.25-S-9891A
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Massage Function Control Unit, Basic Function - GF91.25-S-9891A

Model All (Light transporter) 

Example illustration of massage function control unit 

G16502083Courtesy of MERCEDES-BENZ USA

Overview 

This document contains information on:

General information 

The massage function control unit (1) performs the following tasks depending on the equipment and model involved:

A massage function control unit (1) is installed in the center of the backrest for each seat with a massage function in the seat cushion or in the backrest.

Function requirement 

Function 

The massage function control unit (1) contains integrated valves for supplying air to the massage bladders (3). Targeted actuation of the air bubbles can be used to implement various massage programs depending on equipment installed.

The air supply is provided by the pneumatic pump through the pneumatic pump valve (2).

The massage function control unit (1) is connected to the rear seat row seat adjustment control unit with memory over the CAN.

IMPORTANT If the rear seat seating comfort control unit is installed, the valves of the massage function control unit (1) are not connected as, in this case, the massage function control unit (1) only controls the rear seat seating comfort control unit and the pneumatic pump.

  Component descriptions     
  Component description for massage function control unit Model 447
with code U90 (Left luxury seat of 1st seat row)
with code XM7 (MOPF II)
Model 447
with code U91 (Right luxury seat of 1st seat row)
with code XM7 (MOPF II)
GF91.25-S-5212A