Seat Belt Buckle Switch: Service and Repair

Seat Occupied Sensor

• The front passenger seat occupant sensor (G128) is only installed in the front seat.

Special tools, testers and auxiliary items required

• Hot Air Gun 220 V/50 Hz (VAS 1978/14) only for comfort seats

• Fixture for Seat Repair (VAS 6136)

Removing

• Follow all safety precautions when working on pyrotechnic components. Refer to => [ Restraint System Components ] Description and Operation.

• Before handling pyrotechnical components (for example, disconnecting the connector), the person handling them must "discharge static electricity". For example, by briefly touching the door striker pin.

- Switch the ignition on.

- Disconnect the battery Ground (GND) cable with the ignition switched on.

- Remove the front seat on the passenger side:

• Standard seat and Sport seat (manual), refer to => [ Manual Standard Front Seat ] Manual Standard Front Seat.

• Standard and sport power seat, comfort seat and super sport seat, refer to => [ Power Standard Front Seat ] Power Standard Front Seat.

- Attach the front seat to the (VAS 6136) => [ Installing the Front Seat on VAS 6136 ] Installing the Front Seat On VAS 6136.

- Remove the cover from the cushion (seat pan). Refer to => [ Cover Upholstery, Seat Pan without Seat Depth Adjustor, Separating and Connecting ] Cover Upholstery, Seat Pan Without Seat Depth Adjustor, Separating and Connecting.

• Remove the upholstery from the rear part of the cover until the seat occupied sensor is freed up.

Standard Seat and Sport Seat (Manual or Power):

- Disconnect the seat occupied sensor connector.

- Carefully lift the seat heating element, if applicable.

- Carefully remove seat occupant sensor - 2 - including circuit board - 4 - from seat cushion - 1 -.

Comfort Seat:

- Carefully warm the heating element - 1 - on the left side using the (VAS 1978/14).

- Remove the seat heating element - 2 - - arrow - until the seat occupied sensor - 1 - is freed up.

- Disconnect the seat occupied sensor connector.

- Carefully remove seat occupant sensor - 4 - including circuit board - 3 - from seat cushion - 1 -.

Super Sport Seat:

- Disconnect the seat occupied sensor connector.

- Carefully remove seat occupant sensor - 2 - including circuit board - 4 - from seat cushion - 1 -.

Installing

• Follow all safety precautions when working on pyrotechnic components. Refer to => [ Restraint System Components ] Description and Operation.

• Before handling pyrotechnical components (for example, connecting electrical connector), the person handling them must "discharge static electricity". For example, by briefly touching the door striker pin.

Standard Seat and Sport Seat (Manual or Power):

- Position circuit board - 3 - for seat occupant sensor - 4 - in opening - 2 - in seat cushion - 1 -.

The new seat occupied sensor should be installed in the same location on the seat upholstery as the old seat occupied sensor.

- Align the seat occupied sensor on the seat upholstery according to the markings - a -.

• Dimension - a - = 20 mm.

- Remove the protective film and bond the seat occupied sensor firmly to the upholstery.

Super Sport Seat:

- Position circuit board - 4 - for seat occupant sensor - 2 - in opening - 3 - in seat cushion - 1 -.

- Align the seat occupied sensor on the seat upholstery according to the markings - arrows -.

The new seat occupied sensor should be installed in the same location on the seat upholstery as the old seat occupied sensor.

- Remove the protective film and bond the seat occupied sensor firmly to the upholstery.

Procedure for all seat versions:

Further installation is performed in reverse sequence of removal, but observe the following:

• Make sure the seat occupied sensor is not covered by the seat heater element heating coils.

• Make sure the connectors are installed all the way in and are secure.

Connect the battery with the ignition switched on. Pyrotechnic components could deploy after connecting the battery if they were not repaired correctly. Individuals must not be inside the vehicle when connecting the battery.

- Connect the battery GND cable with the ignition turned on.

• If the airbag indicator lamp (K75) indicates a fault after installation, check the Diagnostic Trouble Code (DTC) memory, erase it and check it again.