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Home >> BMW >> 2021 >> 230i 2D Convertible >> Repair and Diagnosis (Single Page) >> General Information >> OEM General Information >> Functional Description - F22/F23/F87 (2 Of 2) >> Anti-Theft System - Functional Description >> Central locking system >> Brief component description >> Operating facility, hazard warning switch and central locking button
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Operating facility, hazard warning switch and central locking button

The hazard warning switch and the central locking button are combined in a single component.

Using the central locking button, the vehicle can be locked or unlocked from the passenger compartment (prerequisite: both front doors closed).

The following are locked or unlocked:

The fuel filler flap is not locked.

It is not possible to use the central locking button for double-unlocking and deadlocking the fuel filler flap. When the central locking button is pressed, the button signal is forwarded via a direct line connection to the front electronic module (FEM).

If all the preconditions for locking or unlocking are in place, the front electronic module activates the central locking drives in the doors. At the same time the front electronic module outputs the button signal as a message on a bus connection to the rear electronic module (REM). The rear electronic module assumes the task of activating the central locking drive in the tailgate.

The front electronic module (FEM) is the master control unit. In other words, the front electronic module issues the enable for opening the tailgate.

Fig 1: Overview Of Central Locking Button And Hazard Warning Switch
G09872294Courtesy of BMW OF NORTH AMERICA, INC.
Index Explanation
1 Central locking button
2 Hazard warning switch