Seat belt buckle switch

The automatic engine start-stop uses the seat belt buckle switch to identify whether the driver's 3-point automatic-reel belt is closed. If the driver's 3-point automatic-reel belt is not closed, the automatic engine start-stop reacts differently according to the driving condition:

• When the engine is running, a switch-off inhibitor is set and the engine is not stopped.
• If the engine is off the automatic engine start-stop is deactivated. A restart is possibly solely by using the start/stop button.
  Fig 1: Overview Of Seat Belt Buckle Switch

  Courtesy of BMW OF NORTH AMERICA, INC.