Central Locking System

61 01 04 (072)
Central locking system
E87, E90, E91, E92, E93





Introduction
From a functional point of view, central locking system on the BMW 1-Series and 3-Series is divided among several control units. The Car Access System (CAS) monitors all the processes in the central locking system. The CAS control unit is the master control unit for the central locking system.
The control units for the central locking system are:

- Car Access System (CAS)
- Footwell module
- Junction box electronics (JBE)
The CAS control units use the prompts from various operating points (e.g. lock cylinder, remote control, comfort access) to decide what needs to be done:
- Locking/deadlocking the central locking system
- Unlocking the central locking system


Brief description of components
The following components supply an input signal for the central locking system:

- Door lock cylinder
The door lock cylinder allows manual locking/deadlocking and unlocking of the vehicle. If the vehicle electrics should fail, the driver's door can be unlocked manually with the key (mechanical key element in the remote control).

- Door contacts
The signals from the Hall sensors in the door contacts are evaluated by the footwell module (FRM). The antitheft alarm system (DWA), for instance, requires the signals for the purpose of monitoring the doors.
- Remote control
The remote control allows the vehicle to be locked/deadlocked via radio (aerial interface). The radio signals from the remote control are received by the FBD receiver (receiver for remote control) and transferred to the CAS control unit.
> E87, E93
The remote control receiver is integrated in the interior mirror.
> E90, E91, E92
The remote control receiver is integrated in the aerial amplifier.
- Central locking button
The central locking button allows the vehicle to be locked/unlocked from the passenger compartment. The fuel filler flap is not locked.
> E93
The glove compartment and the stowage compartment in the centre console are not locked.
- Hotel position switch (US version)
> E90, E92, E93
The hotel position switch is installed in the glove box. The hotel position switch decouples the tailgate from the central locking system. When hotel position is selected (locked or unlocked), the setting of the hotel position switch is detected.
- Interior tailgate switch (US version)
The interior tailgate switch on the A-pillar in the driver's footwell allows the tailgate to be opened when the vehicle is unlocked and stationary (hotel position not selected).
- Exterior tailgate switch
The exterior tailgate switch allows the boot lid to be opened while the vehicle is unlocked and stationary (hotel position not applied).
> E87
Opening tailgate with BMW logo.
- Boot lid lock
> E90, E92, E93
The tailgate lock allows the tailgate to be mechanically opened (hotel position not selected).
- Rear window button
> E91
The rear window button can be used to open the rear window if the vehicle is unlocked and stationary. The rear window switch is integrated in the rear window wiper.
The following control units are involved in the central locking system:
- CAS: Car Access System
All the rules for controlling the central locking are integrated in the CAS control unit. The commands are sent via the K CAN.
[for more information, please refer to SI Technology (SBT) 61 03 03 019] Car Access System
- JBE: Junction box electronics
The junction box electronics unit is the executing control unit for the central locking system. The
The junction box electronics assume the task of actuating all central-locking system drives.
The junction box consists of the junction box electronics and the electrical distribution centre. The junction box is fitted underneath the glove box.
[for more information, please refer to SI Technology (SBT) 61 05 04 095] Description and Operation
- FRM: Footwell module
The footwell module evaluates the status of the Hall sensors in the door contacts.
When the vehicle is locked or unlocked with the mechanical key element, the footwell module will recognise this request. The footwell module transmits a message on the K-CAN to the CAS control unit (CAS: Comfort Access System).
The footwell module is fitted at the bottom of the A-pillar in the footwell on the driver's side.
[for more information, please refer to SI Technology (SBT) 61 04 04 094]
The following actuators are controlled by the central locking system:
- Door lock
The door locks comprise:
- 2 drives with gearing
- Hall sensors as door contact

- Drives in the door locks
There are 2 drives in each door lock. The locking mechanism can be brought into the following position by the drives:
- Lock: door can still be opened from the inside
- Deadlock: door cannot be opened from the inside or from the outside
- Unlock: door can be opened from the inside and outside
- Drive for fuel filler flap
The drive locks/unlocks the fuel filler flap.
- Drive for the boot lid lock
The drive unlocks the boot lid.
- Drive for rear window lock
> E91
The drive unlocks the rear window.
- Drive for electrically locking glove compartment
> E93
If central locking is activated vie the central locking system, the door lock cylinder or Comfort Access (CA), the drive will block the glove compartment opener.
In this situation, it is only possible to open the glove compartment with the mechanical key.
If the glove compartment was locked with the mechanical key, it can only be opened again with the mechanical key.
- Drive for electric locking of stowage compartment in centre console
> E93
The drive locks the stowage compartment in the centre console.
If the battery is flat or defective, the stowage compartment in the centre console can be opened with a cable.
- Unlocking drive for roller cover
> E91
There is an unlocking drive on the left and right-hand sides of the D-pillar.
To unlock the roller cover, the unlocking drivers are actuated for about 2 seconds by the junction box electronics.

System functions
The central locking system incorporates the following functions:

- Locking
- Deadlocking
- Unlocking
- Hotel position
- Crash unlocking
- Forced deadlock release
- Lockout protection
- Repeat lock
- Automatic relocking
- Voltage monitoring
- Selective unlocking
- Speed-dependent locking
- Locking the fuel filler cap



Locking
A locked door cannot be opened from the outside. However, the door can still be opened from the inside. To do this, the door handle must be pulled twice.
Locking is performed in the following ways:
- Operation of the central locking button (condition: front doors must be closed)
- Operation via the driver's door lock cylinder or the remote control, where the conditions for deadlocking are not fulfilled (see "Deadlocking").
- Driver's door closed



Deadlocking
A locked and secured door cannot be opened either from the inside or outside.
The doors are secured when the driver's door is locked via the locking cylinder (only in conjunction with DWA or CA on the BMW 1-Series) or with the remote control.
Conditions:
- Terminal R OFF
- Driver's door or front-passenger door was opened
- Driver's door closed
When the vehicle is deadlocked, the anti-theft alarm DWA is also primed.



Unlocking
An unlocked door can be opened from the inside and the outside.
When the vehicle is unlocked, the anti-theft alarm (DWA) is also deactivated.



Hotel position (US version)
When the hotel position is selected, the boot lid also stays locked after the vehicle is unlocked. For hotel position to be selected, the setting of the hotel position switch is detected.



Crash unlocking
A crash is recognised as such by the MRS control unit (E87, E90, E91, E92) or ACSM control unit (E93). A crash signal is transmitted by the CAS control unit. The message is sent on the K-CAN. The CAS control unit unlocks the vehicle.
All operating points are disabled when there is a crash signal. This prevents unintentional actions of the central locking system from occurring due to short circuits caused by the accident.
After a crash, the central locking system cannot be operated until terminal R has been switched off for at least 3 seconds.
(MRS = "Multiple Restraint System"; ACSM = "Advanced Crash Safety Module", alternatively known as the "Crash Safety Module")



Forced unlocking
When the CAS detects that a remote control is locked in place in the slot, the central locking system is released. The central locking system adopts the "Locking" position.
The anti-theft alarm is also deactivated during forced release.



Lockout protection
To protect the driver against unintentionally locking himself out, all operating points are locked when the driver's door is open. This makes any additional mechanical lockout protection in the door locks unnecessary.



Repeat interlock
To protect the central locking drives (doors, tailgate, fuel filler flap, rear window, glove compartment and stowage compartment in the centre console) against overloading, the CAS monitors repeat operation.
If there are more than 15 attempts at activation within one minute, the drives are not unlocked for a certain time.



Automatic relocking
If the central locking system is unlocked using the remote control and no door or boot lid is opened within 2 minutes, the vehicle is automatically locked again (locked and secured).
This function can be activated via the personal profile.



Voltage monitoring
The function range for the central locking system is specified as being from 9 to 16 volts. Outside this range, the drives will not be actuated.
If the power supply is interrupted, the status of the central locking system will not change (anti-theft protection).



Selective unlocking
The first time there is an unlocking command, only the driver's door is unlocked. The central locking system sets all other doors from deadlock to lock. The anti-theft alarm system is switched off and the doors remain locked.
The second time there is an unlocking command, the remaining doors are unlocked.
This function can be activated via the personal profile (depends on national version concerned).



Speed-dependent locking
The central locking system is automatically locked from a speed of approx. 16 km/h.
This function can be activated in the Personal Profile (depends on national version concerned).



Locking the fuel filler cap
The fuel filler flap is only locked when the central locking system is set to deadlock.
This function can be activated in the Personal Profile (depends on national version concerned).

Notes for service staff
Service staff should note the following points:

- General information: ---
- Diagnosis: ---
- Encoding/programming: ---
- Programming: ---
- Car and Key Memory: ---
E87, E90, E91, E92, E93: Nearly all Car and Key Memory functions are programmed inside the vehicle itself. (See "Personal Profile" in the Owner's Handbook: Individual settings for up to 3 remote controls via the display in the instrument cluster or via the Central Information Display)
[for more information, please refer to SI Technology (SBT) 00 08 04 108] Description and Operation

National versions
The following details are available with regard to national versions:

- US
The glove compartment is electrically locked. Reason: Knee airbag fitted in glove compartment lid. In order to transmit the forces that are released when the airbags are triggered, the glove compartment lid is bolted on both sides when it is closed.
When the opener is lifted slightly to open the glove compartment, a microswitch transmits a signal to the junction box electronics (JBE). The JBE briefly actuates the unlocking drive in the glove compartment. The unlocking drive retracts the 2 locking bolts. The glove compartment lid can then be opened again.
After a short time, the unlocking drives are de-energised and the locking bolts extend again. The locking bolts have an angled area at the end. This has the effect of mechanically pushing the locking bolts onto a spring when the glove compartment lid is closed. When the glove compartment lid is closed, the spring pushes the locking bolts back out, locking the glove compartment.
Subject to amendment arising from errors, misprints and technical modifications.