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SEATBELT Buckle

Fig 1: Identifying Seat Belt Buckles
GLL152495Courtesy of VOLVO CARS CORPORATION

The two front seat belt buckles have Hall sensors and are connected to the SRS module. These connections are electrically separated from each other.

In some markets, each rear belt buckle also contains a Hall sensor, which is also connected to the supplemental restraint system module (SRS). These connections are electrically separated from each other.

The Hall sensor detects whether the belt is fastened in the buckle and sends information on belt detection to the Supplemental restraint system module (SRS). Information on belt detection is used to adapt the deployment level of airbags and belt tensioners. If a fault is detected in the belt buckles or their connections, there could also be adaption to this depending on the type of fault.