Seat Belt Buckle Switch: Description and Operation

Seatbelt Buckle Switch

The belt buckle switch used in the E65/E66 is a two-wire Hall switch, as already in use in various models since 3/97.

The airbags triggering thresholds are different depending on the crash severity and depending on whether the seatbelt has been fastened or not.

The belt buckle switch is located in the seatbelt buckle on the driver and passenger seat. It is used to detect whether the seatbelt has been fastened or not. The detection arrives as a signal at the relevant satellites. The detection serves to trigger the pyrotechnic actuators in the event of a crash, ( e.g. seatbelt tensioner, airbags etc..)

The belt buckle switch also serves to initiate a seatbelt warning in case the vehicle is started without a seatbelt having been fastened.