Comfort Access: Introduction

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The BMW 1-Series, 3-Series and X5 can be equipped with option 322 "Comfort Access".

This comfort system has been derived from the BMW 7-Series.

From 09/2005, Comfort Access will also be introduced to the BMW 5-Series and BMW 6-Series. The system has been taken from the BMW 3-Series, albeit with a few modifications.

With Comfort Access, an ID transmitter is needed instead of the usual remote control. The ID transmitter also performs standard remote control functions.

Comfort Access can be used to carry out the following functions:

Passive Entry
Opening the vehicle or luggage compartment without actively using the ID transmitter
Passive Go
Engine start without actively using the ID transmitter
Passive Exit
Closing the vehicle without actively using the ID transmitter

Comfort Access prevents an ID transmitter being disabled accidentally.

The CAS control unit is the master control unit for all functions carried out via Comfort Access. Vehicles with Comfort Access are fitted with a CA control unit.

E60, E61, E63, E64
E70
E81, E87, E90, E91, E92, E93

New or modified features on E90, E91, E92 compared to E81, E87, E93:

The detection range of the interior aerials has been modified as a consequence of the different vehicle design.
The remote control (FBD) receiver is integrated into the aerial amplifier. (> E81, E87, E93: FBD receiver integrated in interior mirror)

New or modified for the E60, E61, E63, E64:

The outside door handle electronics is on the reverse of the door handle mounting bracket.
The CA control unit is installed in the carrier behind the glove compartment.

Brief description of components

The following components are described for Comfort Access:

Interior and exterior aerials

Different aerials are required for communication with the ID transmitter: Interior and exterior aerials

The number of aerials depends on the model concerned:

NUMBER OF AERIALS DEPENDS ON THE MODEL

Interior aerials	E60	E61	E63	E64	E70	E81	E87	E90	E91	E92	E93
Front center console	x	x	x	x	x	x	x	x	x	x	x
Rear center console	x	x	x	x	x	x	x	x	x	x	x
Rear window shelf (parcel shelf)	x	-	x	-	-	-	-	-	-	-	-
Back of rear seat	-	x	-	-	-	-	-	-	-	-	-
Luggage compartment, middle	x	-	x	x	-	x	x	x	x	x	x
Luggage compartment, right	-	-	x	x	x	-	-	-	-	-	-
Luggage compartment, left	-	-	-	-	x	-	-	-	-	-	-
Luggage compartment, load edge	-	x	-	-	-	-	-	-	-	-	-
Exterior aerials	E60	E61	E63	E64	E70	E81	E87	E90	E91	E92	E93
Rear bumper, left	x	-	x	x	-	-	-	-	-	-	-
Rear bumper, middle	-	x	-	-	x	x	x	x	x	x	x
Outside door handle electronics	4	4	2	2	4	2	2	2	2	2	2

The aerials emit 125 kHz radio signals which are evaluated by the ID transmitter.

Outside door handle electronics
The number of outside door handle electronic units depends on the model concerned (see table above).

The 3 sensors in the outside door handle electronics send the following signals to the CAS control unit and the CA control unit:
- Unlock: When a hand reaches into the handle recess via capacitive sensor 1
- Unlock: When a hand pulls on the outside door handle via tension sensor (redundant to capacitive sensor 1)
- Locking and deadlocking: On contact with the sensitive area of the door handle via capacitive sensor 2
A built-in aerial also sends radio signals in order to check for an ID transmitter located on the outside of the driver's door or front-passenger door.
- E70, E81, E87, E90, E91, E92, E93
The outside door handle electronics are installed in the outside door handle.
- E60, E61, E63, E64
The outside door handle electronics are behind the grip recess plate.
ID transmitter
The ID transmitter evaluates the signals from the aerials. It also sends high-frequency radio signals to the FBD receiver.

Inserting the ID transmitter into the slot deactivates all Comfort Access functions.
Remote control receiver for remote control services
- E64, E81, E87, E93
The remote control receiver is integrated in the interior mirror.
- E60, E61, E63, E70, E90, E91, E92
The remote control receiver is integrated into the aerial amplifier.

The remote control (FBD) receiver picks up radio signals from the ID transmitter and forwards them to the CAS control unit. The Comfort Access control unit (CA control unit) activates the FBD receiver.
CAS control unit
The CAS control unit (CAS: Car Access System) is the master control unit for all Comfort Access functions.

The CAS control unit is the interface to the START/STOP button and to the slot for the ID transmitter. The electronic steering lock is also activated by the CAS control unit.

The CAS control unit is connected with the following components via the K-bus (sub-bus):
- Outside door handle electronics (number depends on model concerned)
- Comfort Access control unit (CA control unit)
- Electronic steering lock
When the vehicle is idle, communication may take place on the K-bus without waking up the vehicle.
START/STOP button
The START/STOP button can be used to switch the terminals in sequence (0, R, 15, R, 0). The engine can be started by depressing the clutch or the brake (manual transmission/automatic transmission) and pressing the START-STOP button.
Slot for the ID transmitter/remote control
- On vehicles without Comfort Access:
  In order to start the engine, the remote control must be latched in place in the slot.
- On vehicles with Comfort Access:
  The remote control must be inserted into the slot if the battery in the ID transmitter is discharged. The engine can then be started up.
  
  Inserting the ID transmitter into the slot deactivates Comfort Access.
JBE: Junction box electronics
- E70, E81, E87, E90, E91, E92, E93
The junction box electronics activates the central locking system.

If the CAS control unit approves the unlocking of the vehicle, for example, the doors will be unlocked.
KGM and KBM: Body gateway module and body basic module
- E60, E61, E63, E64
The body gateway module actuates the central locking in the front doors.

The body basic module controls the central locking in the rear doors.

If the CAS control unit approves the unlocking of the vehicle, for example, the doors will be unlocked.
Comfort Access control unit
The Comfort Access control unit (CA control unit) actuates the internal and exterior aerials.

An ID transmitter scan is carried out. At the same time, the FBD receiver is activated for any ID transmitters which may respond.
- E60, E61, E63, E64
- E70
- E81, E87, E90, E91, E92, E93