Seat Adjustment Driver's Side, Passenger Side

Seat adjustment driver's side, passenger side
Depending on equipment, the following adjustments to the seats are possible:

Seat fore/aft adjustment

Seat height adjustment

Seat angle adjustment

Seat depth adjustment

Seat angle adjustment

Backrest width adjustment

Headrest adjustment

Headrest adjustment

Brief description of components
Seat module driver's side/passenger side
Depending on equipment, the seats are equipped with different seat modules. In general, there are 2 different module sizes:

Module with 10-chamber plug connection

Module with 8-chamber plug connection

If the seat is equipped with the special equipment lumbar support adjustment or Active Seat, the module is fitted with a 10-chamber plug connection.

The seat module is secured directly to the corresponding seat.

The seat modules are networked with the vehicle via the CAN BUS.

Center console switch center
The control module center console switch center has the following functions:

CAN BUS interface to the vehicle electrical system

Interface to the seat switches

Interface to the controller

The control module center console switch center is fitted in the front center armrest.

Operating switch driver seat/passenger seat
Depending on the equipment, various switch blocks are fitted.

The switch blocks are connected by means of ribbon cables to the center console switch center (BZM).

Hall sensors, seat position
With the seat memory equipment, servomotors with Hall sensors are fitted.

Main functions
Seat adjustment
The seats are adjusted by operating the corresponding switch.

The adjustment command is transferred from the switch block to the BZM across a ribbon cable.

The BZM sends the message across the K-CAN SYSTEM to the Car Access System (CAS).

The CAS as �gateway control module� passes the message on to the corresponding seat module via the K-CAN PERIPHERALS.

The seat module activates the adjustment motor directly via its final stages. Simultaneously, a maximum of 3 motors are activated.

The total running time of each adjusting motor is monitored to prevent thermal overloading. When a mechanical stop is reached, the activation is stopped. The mechanical stop is detected via the increased current intake.

In the case of the Memory seat, the position of the mechanical stops is saved after the first identification. For subsequent adjustments, the seat stops before this position is reached (soft stop).

In the case of comfort seat, 4 adjustment directions are equipped with soft start:

Seat fore/aft adjustment

Seat angle adjustment

Seat height adjustment

Seat angle adjustment

Headrest
The headrest is a function of the longitudinal seat adjustment.

The headrest is automatically readjusted:

mechanically with an operating cable in the case of basic seat,

electrically in the case of comfort seat (by identifying the position using Hall sensors). Here, the headrest moves to the corresponding position as soon as the longitudinal adjustment has been completed. In addition, the headrest can be electrically adjusted on an individual basis.

Seat memory
The seat memory control module provides the possibility to store various seat positions.

To run the stored seat position, the seat memory control module requires information:

Key number from the CAS

Memory key of BZM

The information is simultaneously sent to the following control modules:

the front door modules for the mirror memory position

the CIM (Chassis Integration Module) for the steering column memory position

Operation of the seat memory
Programming

Seat positions can only be programmed as of terminal R.

Saving a seat position:

Press the memory key �M�: The programming readiness is active for 7 seconds.
Programming readiness is indicated by the memory button lighting up.

Press position button: adoption of current position of seat, steering column and rear view mirror.

Retrieval

A distinction is made between two operating modes when stored driver seat positions are retrieved:

Touch button operation: Touching the desired position button causes the drives to move into the corresponding position. The one-touch function is only possible with terminal 15 off.

Continuous button operation: The drives only run as long as the desired position button is pressed. If the button is released before the target position is reached, the drives are switched off immediately. The positioning procedure is continued when the position button is pressed again.