Central locking

The central-locking system is controlled by the general module 5.

The central locking drives in the vehicle doors are integrated in the system lock and facilitate locking, arming and unlocking of the doors.

In additional, the following flaps and compartments are locked and unlocked by means of the central-locking drives:

E46 Saloon, Coupé, Touring: fuel tank flap

E46 Convertible: fuel tank flap and glove compartment

E52 Z8: glove compartment and storage shelf in centre console

E83 X3: fuel tank flap

E85 Z4: fuel tank flap and storage shelf (with soft top cover)

Functions

General

A differentiation is made between locking and locking with arming with regard to the functions of the central locking system.

Locking without arming:The vehicle doors can be opened from the inside by pulling the door handle twice.

Locking with arming:The vehicle doors can be opened neither from the inside nor the inside.

”Locking with arming” is implemented when:

• The ignition lock is in position 0 and the vehicle key is removed.
  
• The driver's or passenger's door is opened after removing the key
  
• The driver's and passenger's doors are closed
  
• The vehicle is locked via the door lock or remote control
  

Central double-locking of the vehicles also locks the flaps and compartments fitted with central-locking drives (see above).

Central locking drives

The drives are activated by a relay in the general module.

The general module is equipped with a repeat inhibit function in order to protect the drives from thermal overload as the result of frequent use.

Operating points

The central locking system can be operated from following points:

• Door lock of driver's door
  
• Door lock of passenger's door (only if no remote control is installed)
  
• Remote control (country-specific radio or infrared remote control)
  
• Centerlock button (central locking button) in vehicle
  

The vehicle can only be locked and unlocked with the Centerlock button, i.e. not armed and disarmed.

Note:Remote control functions are executed only if there is no key inserted in the ignition lock.

Automatic unlock

The vehicle doors are unlocked automatically when the airbag control unit detects a crash. Crash signalling is performed:

• with airbag control unit MRS2 via the CS line from the airbag control unit to the general module.
  
• from airbag control unit MRS3 via the K bus.
  

After crash detection, the central locking system must be unlocked once before locking is possible again.

An armed vehicle is disarmed automatically (not unlocked) when the vehicle key is inserted in the ignition lock. This status is detected by the control unit of the ”electronic vehicle immobilisation system (EWS)”.

Selective release

The following function can be coded via car key memory or is coded as standard in some country-specific variants (e.g. USA):

Initially only the driver's door is unlocked if a locked vehicle is unlocked by means of the door lock or remote control. All other doors are switched from the armed status to the disarmed status, however, they are not unlocked (it is possible to unlock the doors using the inner door handle or Centerlock button). The doors are unlocked when the vehicle is unlocked for a second time via the door lock or remote control.

Automatic lock

The following function can be coded via car key memory or is coded as standard in some country-specific variants (e.g. USA):

The doors are locked automatically on exceeding a driving speed of 4 km/h.

Emergency operation

In the event of electrical operation failing (e.g. discharged batteries) the door can be unlocked mechanically via the door lock.

Boot lid

Operation of the boot lid/tailgate and rear window (E46 Touring) depends on the status of the central locking system.

When the vehicle is locked, the boot lid/tailgate/rear window can only be opened using the remote control.