BMW 7 Series: System Components

Components of the Central Locking System

Footwell Module

The footwell module is installed at the left-hand A-pillar. It evaluates the status of the door contacts and reads in the Hall sensor signals of the lock barrel in the driver's door and transfers the information via the K-CAN2 to the junction box electronics module or Car Access System 4.

Car Access System 4

The Car Access System 4 is installed on the right, above the steering column. It assumes the master function for the central locking system. The Car Access System 4 has the exclusive system authorization and is simply supported by the other control units.

The Car Access System 4 also registers the status of the center lock button. The Car Access System 4 activates central locking, depending on the status of the central locking system. Briefly pressing the center lock button triggers the vehicle to lock or unlock.

The Car Access System evaluates the status of the interior trunk button on the A-pillar and the central locking button on the trunk.

Junction Box Electronics Module

The junction box electronics module is plugged into the front power distribution box.

NOTE: The power distribution box and the junction box electronics module are two separate components. This must be borne in mind when performing service work.

The junction box electronics module contains the relays for activating the central locking drive units.

The trunk central locking is activated via a power output stage in the junction box electronics module.

The status of the exterior trunk button is read by the junction box electronics module and this information is passed on to the Car Access System 4.

The automatic soft-close drive and the remote control receiver are supplied with power by the rear power distribution box.

Controls

The central locking can be operated from the following controls (among others):

• ID transmitter
• Driver's-door/trunk lock barrel
• Central locking button
• Interior trunk button in the A-pillar
• Central locking button.

ID transmitter

Each vehicle is supplied with a purse key/spare key and two ID transmitters. The adapter for the spare key is located in the glove compartment.

NOTE: Up to eight ID transmitters can be used in conjunction with the Comfort Access function. Four ID transmitters can be used for personal profiles.

The ID transmitter has one button for locking and one for unlocking the vehicle. There is a separate button for unlocking the trunk. Pressing the trunk symbol button triggers automatic closing/opening of the trunk.

Automatic closing requires the automatic trunk actuation option.

The ID transmitter contains a battery which lasts up to four years.

The mechanical key is located in the ID transmitter.

NOTE: The passenger airbag can also be deactivated/activated with the mechanical key.

Fig. 14: Identifying F01/F02 ID Transmitter

COMPONENTS DESCRIPTION CHART

1. ID transmitter top view
2. Unlock/comfort open
3. Lock/comfort close
4. Button for OPEN trunk
5. Button for vehicle search function
6. ID transmitter rear view
7. Transponder coil area
8. Battery compartment
9. Button for mechanical key
10. Mechanical key

The ID transmitter has a 512 MB data memory. The following data can be stored in the ID transmitter:

ID TRANSMITTER DATA

NOTE: The remote control receiver is integrated in the antenna diversity facility and passes the remote control signal to the Car Access System 4 via the LIN bus.

Driver's-door lock barrel

The lock barrel is connected mechanically via a linkage to the door lock. Hall sensors for the lock barrel are integrated in the door lock.

The footwell module evaluates the signals from the Hall sensors for locking/unlocking purposes.

Trunk locking barrel

The lock barrel is connected mechanically via a Bowden cable to the trunk lock. Turning the spare key in the lock barrel opens the trunk lock.

NOTE: If the vehicle is fitted with an anti-theft alarm system, this causes an alarm to be triggered. 1 Center lock button 2 Center lock button.

Center-lock button

The center-lock button is installed between the center of the outlets in the dashboard. The center-lock button forms one unit together with the hazard warning lights button.

Fig. 15: Identifying F01/F02 Button Unit

CENTRAL LOCKING BUTTON REFERENCE CHART

1. Hazard warning flasher button
2. Central locking button

NOTE: The center lock button can also be operated when the vehicle is locked.

However, opening the vehicle door will trigger an alarm from the anti-theft alarm system.

Central Locking Drive Units

A central locking drive unit consists of an electric drive unit and the unlocking/locking mechanism.

The central locking drive units in the doors are equipped with two motors to facilitate the unlocking/locking and central arrest functions of the vehicle.

Central arrest means that the locking button in the doors is separated mechanically from the central locking drive unit.

As a result, the vehicle cannot be opened by pulling the locking button.

The Hall sensor for the door contact is additionally integrated in the central locking drive unit.

Trunk central locking drive (trunk lock)

The central locking drive for the trunk is equipped with a motor for unlocking.

The central locking drive contains two microswitches which are actuated by the locking pawl. If the locking electronics in the automatic soft-close drive register the status and activate the drive. As soon as the locking pawl engages in the main locking position, the drive stops.

NOTE: The junction box electronics module evaluates the status of the microswitch.

The junction box electronics module sends the status via the K-CAN2. This applies to vehicles with automatic trunk actuation. The trunk lift requires this information so that it can start at the right time, and not cause damage to the trunk lock.

The second microswitch is used to switch on the luggage compartment lighting. The change in the status of the microswitch which occurs when the trunk is opened or closed is also used to monitor the trunk for the purposes of the anti-theft alarm system.

The automatic soft-close drive is connected to the trunk lock with a Bowden cable. This has the benefit that the drive can be fitted regardless of the available installation space. The drive is connected to terminal 30B. The fuse is located in the rear power distribution box. An electronics module is integrated into the automatic softclose drive which is used to monitor its proper functioning.

Closing the trunk places the rotary striker in the trunk lock in the pre-locking position. To this end, a microswitch is located in the trunk lock which changes status when the lock is actuated.

The electronics module in the automatic soft-close drive evaluates this change in status and triggers the drive to switch on. The automatic soft-close drive is actuated until the rotary striker is located in the main locking position. Once this has occurred, the microswitch changes status again and the drive is switched off.

NOTE: The drive and the trunk lock can be replaced individually.

Fuel filler flap central locking drive

The central locking drive is equipped with a motor for unlocking/locking.

Manually releasing the fuel filler flap

The fuel filler flap can be released manually in the event of an electrical defect. The release mechanism is located in the luggage compartment, on the right-hand side.

Manually Unlocking the Trunk

The US variant of the F01/F02 has an emergency trunk release mechanism. This makes it possible to open the trunk manually from inside the luggage compartment.

Fig. 16: Identifying F01/F02 Emergency Trunk Release Mechanism

COMPONENTS DESCRIPTION CHART

1. Trunk lock
2. Handle for the emergency release
3. Automatic soft-close drive
4. Trunk lock barrel mechanism

Pulling on the handle (item no. 2) unlocks the trunk lock. The pulling motion on the handle is transferred to the trunk lock by a Bowden cable, causing the trunk lock to unlock.

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