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Seat Belt Warning, Basic Function - GF91.60-P-1001A

MODEL ALL (CAR) 

Overview 

This document contains the following information:

General 

The seat belt reminder continuously checks whether the vehicle occupants are wearing their seat belts. To do so, it monitors the status of the individual seat belt buckles. If one of the occupants is not strapped in, the seat belt reminder provides a visual warning and a warning tone (seat belt warning), depending on country.

Function requirement 

Seat belt reminder warning 

For the seat belt warning, the seat belt reminder evaluates information on the status of the individual seat belt buckles.

The seat belt reminder message for the front passenger is only issued if the front passenger seat is occupied.

The rear seat belt reminder warning is always output as of 6 km/h. After 5 s or after acknowledgment, the rear seat belt reminder warning disappears. The rear seat belt warning does not have any effect on the deployment behavior of the restraint equipment; it only serves as information for the driver.

The nature and method of the warning output varies depending on whether or not the seat belt warning is required by law. It is included in the evaluation by the New Car Assessment Program (NCAP). NCAP is a program for assessing the safety of new vehicles.

In countries in which the seat belt reminder warning is prescribed by law (extended NCAP), the seat belt warning indicator is actuated for a period of 6 ± 2 s. It is irrelevant here whether the driver seat belt is fitted or not. If the driver's seat belt is not fastened, the system also outputs a warning tone.

IMPORTANT If the driver seat belt is fastened in the meantime, the acoustic warning is muted.

Meanwhile, there is no evaluation of whether or not the front passenger seat belt is fastened. Only after 6 s are the statuses of both seat belt buckles evaluated.

In countries in which the seat belt warning is not prescribed by law, the seat belt warning indicator is only actuated during the self-test.

As soon as the engine is detected to be running ("Engine running" or "Drive train ready" signal set), information on the statuses of the driver and front passenger seat belt buckles is evaluated. If a seat belt is recognized as not being fitted, the seat belt warning indicator lights up. If the vehicle then starts to move off, several acoustic warning phases are run through when a speed of 25 km/h is reached.

Depending on the type of seat belt warning issued, three or four acoustic warning phases are issued in succession. During these acoustic warning phases, the seat belt warning indicator is actuated to flash at a frequency of 2 Hz. When all the acoustic warning phases have finished, the seat belt warning indicator is actuated permanently.

Acoustic warning phase 1: 

If the vehicle drives off, acoustic warning phase 1 starts to run in the background. When a speed of 25 km/h is reached, a quiet warning tone is issued at intervals of 4 s. Acoustic warning phase 1 lasts for 20 s. Acoustic warning phase 2 is then started.

Acoustic warning phase 2: 

When acoustic warning phase 1 has finished and a speed of at least 25 km/h is reached, a quiet warning tone is issued for 20 s at intervals of 2 s. Acoustic warning phase 3 is then started.

Acoustic warning phase 3: 

When acoustic warning phase 2 has finished and a speed of at least 25 km/h is reached, a quiet warning tone is issued for 20 s at intervals of 1 s. Acoustic warning phase 4 is then started.

Acoustic warning phase 4 (Euro NCAP only): 

When acoustic warning phase 3 has finished and a speed of at least 25 km/h is reached, a loud warning tone is issued for 93 s at intervals of 0.5 s.

Cancellation of seat belt reminder warning: 

Seat belt reminder warning reactivation: 

  Subsystems     
  Front passenger seat seat occupancy recognition, basic function   GF91.60-P-1006A
  Control units     
  Head unit/instrument cluster display cluster, basic function   GF54.30-P-2005A
  Instrument cluster control unit, basic function Model all (CAR)
with code 548 (Connect 20 MID (NTG6))
Model all (CAR)
with code 549 (Connect 20 HIGH (NTG6))
GF54.30-P-9891A
  Head unit/instrument cluster control unit, basic function Model all (CAR)
with code 545 (Connect 5 (NTG6))
GF82.85-P-9893A
  Supplemental restraint system control unit, basic function   GF91.60-P-9890A 
  Components     
  Seat belt buckle switch, basic function   GF91.60-P-2009A