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Comfort Access



Comfort Access

Comfort Access
The Comfort Access function is an optional equipment.

The system has the following characteristics:
- no outside door handle electronics with sensors and aerial
- Operated via a button in the outer door handle
- Exterior aerial for the doors in the inner side trim panel behind the B-pillar

With Comfort Access, an ID transmitter is required instead of the usual master key. The ID transmitter continues to fulfil all functions of the remote key. The following functions are available with Comfort Access:
- Access authorization
Unlocking the vehicle or the tailgate only without active use of the ID transmitter
- Drive authorization
Engine start without active use of the ID transmitter
- Locking authorization
Locking the vehicle without active use of the ID transmitter (including convenient closing)

Comfort Access prevents inadvertent lockup of an ID transmitter. A second valid ID transmitter is located outside.

Brief component description
The following components are described for Comfort Access:

Vehicle interior aerials and vehicle exterior aerials
Various aerials are required for communication with the ID transmitter: Interior aerial and exterior aerial. The exterior aerials for monitoring the doors are behind the side trim panel. The MINI has no aerials in the outer door handle.







The aerials transmit on a frequency of 125 kHz. The wave emitted by the aerials are near spherical in form. The ID transmitters are asked to identify themselves via the aerials. All the radio signals are encrypted and thus protected against unauthorized access.
The interior aerials and exterior aerials are made of ferrite.

Button in outer door handle
There is a button on both the driver's and front passenger's doors. This button unlocks and locks the vehicle.







The outer door handle buttons are connected to the Comfort Access control unit. Pressing the button starts an authentication procedure (= check for authorized ID transmitter).

ID transmitter
The ID transmitter evaluates the signals from the aerials. It also sends high-frequency radio signals to the remote control receiver (868 MHz/315 MHz, country-specific).Inserting the ID transmitter into the fixture deactivates all Comfort Access functions.







As opposed to the remote key, the ID transmitter on optional equipment 322 "Comfort Access" has a battery. The battery is needed for the following reasons:
- Recharging must not be needed, increasing convenience (e.g. by inserting in the fixture or from external charging station).
- The ID transmitter consumes more power than the remote key.
- The ID transmitter battery has a significantly higher capacity with a longer life.
An integrated mechanical key is provided to open or close the vehicle manually in an emergency (e.g. flat battery or local radio interference).

Receiver for remote control services
The receiver for remote control services (remote control receiver) is in the inside mirror. The FBD receiver receives the radio signals from the ID transmitter. The FBD receiver forwards these signals to the CAS control unit. The Comfort Access control unit (CA control unit) activates the FBD receiver.

START/STOP button and fixture for the ID transmitter/remote key
The START/STOP button can be used to switch the terminals (0, R, 15, R, 0) on a rolling basis. The engine can be started by depressing the clutch or the brake (manual gearbox/automatic transmission) and pressing the START/STOP button. Prerequisite: a valid ID transmitter has been detected.







For vehicles without Comfort Access: The remote key must be locked in the fixture to start the engine. For vehicles with Comfort Access: The remote key must be inserted in the fixture if the ID transmitter battery is flat. The engine can then be started up. Inserting the ID transmitter into the fixture deactivates Comfort Access.

CAS: Car Access System
The CAS control unit is the master control unit for all functions run by Comfort Access. The CAS control unit is the interface to the START/STOP unit. The START/STOP united comprises the START/STOP button and the ID transmitter fixture. The electric steering lock is also activated by the CAS control unit. The CAS control unit is connected through the body bus (sub-bus) to the following:
- Control unit for Comfort Access (CA)
- Electric steering lock (ELV)







The CAS control unit is also connected to the CA control unit through the body controller area network. When the vehicle is in a rest state, communication may take place on the body bus without waking up the CAN bus system.

JBE: Junction Box Electronics
The junction box electronics are the executing control unit for the central locking system. The JBE assumes responsibility for activating all central locking drives. For example, if the CAS control unit authorizes the unlocking of the vehicle, the doors are unlocked. The JBE also supplies the Comfort Access control unit using the closed-circuit current cut-off relay.

System functions
The following system functions are described for Comfort Access:
- Access authorization via the driver's door or front passenger door
- Access authorization via the tailgate
- Drive authorization
- Locking authorization
- Locking an ID transmitter inside the vehicle
- Misuse protection
- Personal Profile

Access authorization via the doors
The vehicle is unlocked at the push of a button. Precondition: The ID transmitter must be located no further than 1.5 m from the aerial in the outer door handle. Ideally, the user carries the ID transmitter in his or here pocket. First, the user is authenticated (= authenticity check). It is taken for granted that the data transferred on authentication is encrypted. If the ID transmitter authenticity check is successful, the user will be granted access authorization to the vehicle. The central locking system is unlocked. The door can be opened. The authentication procedure for locking authorization and drive authorization is principally the same.

Authentication procedure with access authorization as an example:
- Trigger signal from button in outer door handle.
- CA control unit detects the trigger signal through the body bus. CA control unit permanently switches on the remote control receiver.
- CA control unit is requested by the CAS through the body controller area network to search for an ID transmitter using the exterior aerials in the side trim panel. All ID transmitters associated with the vehicle and located outside of it are included in the search (low-frequency radio signal at 125 kHz). The search determines whether an ID transmitter associated with the vehicle is located in the operating range of the aerials in the outer door handle.
- The CA control unit communicates simultaneously with the CAS control unit through the sub-bus (body bus).
- All ID transmitters send a radio signal via the FBD receiver to the CAS control unit (high-frequency radio signal, depending on the country e.g. 868 MHz).
- The CAS control unit decides which of the logged-in ID transmitters is used for the rest of the authentication procedure.
- This selection is sent in a message through the body bus to the CA control unit. At the same time, the CA control unit is requested to send a selective prompt to the ID transmitter concerned.
- The ID transmitter that receives the selective prompt responds by sending a radio signal via the FBD receiver to the CAS control unit (high-frequency radio signal with 868 MHz).
- The CAS control unit evaluates the feedback signal and - if the feedback signal is valid - gives the access authorization. The vehicle is unlocked.

Access authorization via the tailgate
With Comfort Access, the luggage compartment can be opened without active use of the ID transmitter. Precondition: The ID transmitter must be located no further than 1.5 meters from the aerial in the rear bumper. Ideally, the user carries the ID transmitter in his or here pocket. The rear lid button must be held for approx. 500 ms to open the luggage compartment. If an ID transmitter is in the vicinity of the rear end, the tailgate opens. If an ID transmitter is located inside the luggage compartment when the tailgate is closed (and there are no authorized ID transmitters outside the vehicle), the tailgate will open up again.The attention of the user is drawn to the anti-theft alarm system as follows:
- visual signal via turn indicators (basic version)
- acoustic signal via emergency power siren, US version only (for optional equipment 302)

Drive authorization
In order to switch the terminal and/or start up the engine, the ID transmitter must only be located inside the passenger compartment (not necessarily in the fixture).The luggage compartment is classed as part of the passenger compartment in the R56. In principle, the authenticity check required is the same as that for access authorization (except that it is run via the interior aerials). If there are no ID transmitters inside the vehicle when the START/STOP button is pressed: Check Control message in the instrument panel. The terminals are switched when the START/STOP button is pressed. The sequence is: 0 - terminal R - terminal 15 - terminal R - 0. To start the engine, the START/STOP button must be pressed briefly.The clutch pedal or brake pedal (manual gearbox or automatic gearbox respectively) must be depressed at the same time. An engine start is possible in any terminal position. Once the engine has been switched off, it may be restarted within 10 seconds even if no ID transmitter is detected inside the passenger compartment (i.e. no valid drive authorization). This safety precaution is required for any possible emergencies. Exception:if a door is opened within the 10 seconds, this after-run is cancelled immediately.

Locking authorization
The outer door handle button must be pressed and held for approx. 500 ms to lock and then secure the vehicle.If the locking button is held for approx. 3 seconds, convenient closing will start. This means the side windows and slide/tilt sunroof will close. Convenient opening via the outer door handle is not possible. Terminal R is deactivated when the outer door handle is locked. Terminal 15 is not deactivated when the vehicle is locked. A Check Control message appears and a warning tone sounds if the driver's door is opened with terminal 15 ON.Special feature: Comfort Access allows the vehicle to be locked whilst the engine is running.

Locking an ID transmitter inside the vehicle
When the vehicle is locked via the outer door handle, any ID transmitter inside the vehicle will be detected.The search of the passenger compartment is started when the last door is closed. This ID transmitter is blocked for locking authorization (not for drive authorization). The ID transmitter is reactivated when terminal R is ON or when the central locking system is unlocked.

Cycle protection
The vehicle may only be locked and unlocked consecutively a maximum of 15 times. After this, the tamper-proof lock is activated. Operation is disabled for 10 seconds. The cycle protection is deactivated completely after 4 minutes. Once again, the vehicle may then only be locked and unlocked consecutively a maximum of 15 times. Cycle protection is also enforced if the tailgate is unlocked and locked in quick succession. The ID transmitter may also be locked in the luggage compartment (= passenger compartment).

Personal Profile
The customer can make the following individual settings for unlocking the vehicle on the driver's door:
- door-selective, i.e. only the driver's door
- all doors together

For vehicles without Car Communication Computer: Personal Profile is set on the steering column switch for the turn indicators (via on-board computer). The menu guidance is in the KOMBI2 liquid crystal display on the steering column.
For vehicles with Car Communication Computer: Personal Profile is set using the CON on the central information display (CID).
If the vehicle was unlocked on a door-selective basis, the remaining doors can be unlocked using the centre lock button.

NOTICE: No Personal Profile is possible for the front passenger door.

Pressing the button on the front passenger door will always unlock all doors.

Notes for Service department

General notes

NOTICE: Voltage supply for the ID transmitter.

Two factory-fitted ID transmitters are available for each vehicle. The ID transmitter has a battery. The battery service life is approximately 2 years. The battery compartment is on the rear side of the ID transmitter. When the battery is almost completely discharged, the driver is informed by a Check Control message. If the Check Control message is ignored, the ID transmitter made inoperative (for data backup).

NOTICE: Mechanical ignition key integrated in ID transmitter.

In emergencies, e.g. local interference, the vehicle can be opened using the integrated key in exactly the same way as the remote key.

NOTICE: Data for Condition Based Service.

The CBS data is always written to the ID transmitter when terminal 15 is ON and the vehicle has been driven over 10 kilometers. The data is sent by radio (aerial for Comfort Access). A hidden function is available for updating the CBS data. To do so, switch on terminal 15. Then press and hold down the centre lock button. Then press the START-STOP button. When the ID transmitter is in the fixture, the CBS data is updated in cycles.

NOTICE: Move automatic transmission lever to "P" position.

"P" must be engaged on vehicles with automatic transmission in order to stop the engine.

NOTICE: When in car wash only.

When entering a car wash: Follow the notes in the Owner's Handbook for vehicles with automatic transmission.

Diagnosis instructions
Observe the following information for diagnoses of the Comfort Access:

Resetting the Car Access System
The CAS does not have to be reset after working on the door handles.

Notes on encoding/programming
An initialization must be carried out after the Comfort Access control unit has been changed. The terminal change after terminal 15 ON triggers the initialization. The CAS control unit automatically initializes the Comfort Access control unit.

National-market version
The frequency of the radio signal from the ID transmitter is country-specific: It also sends high-frequency radio signals to the remote control receiver (868 MHz/315 MHz, country-specific).
We can assume no liability for printing errors or inaccuracies in this document and reserve the right to introduce technical modifications at any time.