Keyless Entry: Description and Operation
Infrared Locking System (IR):Functional Description:
General:
With the infrared locking system (IR), the vehicle can be locked, unlocked or arrested via the central locking system. The antitheft system (DWA) is armed when the vehicle is in arrest mode. The windows and sunroof are closed automatically (only power windows and sunroof) when the lock button is pressed for at least 2 seconds.
The infrared functions are performed only when the ignition is off. The infrared functions are performed in conjunction with the ZKE control unit or the antitheft system (DWA).
The infrared transmitter also contains the conventional, mechanical key. The key folds out to the side when the BMW emblem is pressed. All central locking functions can still be operated with the key.
The infrared system operates at a distance of up to 5 to 6 meters. There must be no solid objects between the transmitter and the receiver in the vehicle.
The IR system is theft-proof. Manipulations are not possible.
Components:
Transmitter (key): Battery operated (commercially available round cells) IR transmitter.
Receiver: Place of installation, front vehicle roof. Receives and amplifies the signals from the transmitter and transfers them to the logic module.
7 Series: One receiver is used.
5 Series: Two receivers (switched in parallel) are used.
Logic module: Place of installation, rear power distributor. Control unit of the infrared system. Processes the signals and gives the ZKE control unit or the ZV module or the antitheft system (DWA) the required command (lock, unlock, arrest etc.).
Indicator: Place of installation: Ventilation grille. The transmitter is initialized via the indicator. If an antitheft system (DWA) is installed, it also contains the LED indicator for the antitheft system (DWA).
Buttons on the IR Transmitter:
Transmitter version up to model year 1988:
Button 1 (front): Unlock vehicle, disarm antitheft system (DWA), switch on interior lights.
Button 2 (rear): Lock vehicle, close windows/sunroof.
Button 3 (side): Arrest vehicle, arm antitheft system (DWA), close windows/sunroof. All functions are performed only within 15 seconds after pressing the button 2.
Transmitter version as of model year 1989:
A new IR transmitter has been introduced together with model year 1989. The new transmitter is more effective and the buttons 1 and 2 have been interchanged. The command unlock/disarm DWA is sent 5 times in succession when the unlock button is held pressed. In this case, the LED lights briefly 5 times.
Button 1 (front): Lock vehicle! Close windows/sunroof.
Button 2 (rear): Unlock vehicle, disarm antitheft system (DWA), switch on interior lights.
Button 3 (side): Arrest vehicle, arm antitheft system (DWA). The functions are performed within only 15 seconds after pressing button 2.
The function "close windows/sunroof" is now only triggered by the lock button, and no longer by the button 3 (side).
Note on Interior Light:
The infrared system switches ground to the ZKE input door handle contact. All repeat lockouts and switch-on conditions are effective. Refer to Section ZKE Interior Lights).
Function Indication on the Transmitter:
Lights briefly - after a button has been pressed: Transmitter is OK.
Quick flashing - when button 2 or 3 is held depressed: Command close window/sunroof is performed.
Slow flashing - during initialization, indicates transmitter is initialized.
Lights continuously - after the transmitter self-test, transmitter is OK. See Transmitter Self-test.
Does not light - after pressing a button: Renew batteries
Transmitter Self-Test:
Hold transmitter directly against a bright surface (e.g. white paper). Press unlock button and hold.
The self-test begins after the unlock code has been transmitted (LED lights briefly, in the case of transmitter as of model year 95, 5 times in succession). The transmitter is in perfect working order if the LED then lights for approx. 5 seconds (continuous light).
In the case of fault, renew battery. If batteries are OK., renew the transmitter.
Initialization:
It is necessary to initialize the transmitter:
- When the transmitter had no power supply for more than 1 minute
- When the transmitter is new
Initialization is not necessary:
- When changing the batteries in the transmitter within one minute (capacitor buffer)
- Interruption in power circuit in the vehicle
Procedure:
- 1. Switch on ignition in vehicle with second key.
- 2. Place transmitter directly on display, hold straight (LED must face towards the operator).
- 3. Press unlock button until the LED on the transmitter begins to flash slowly. The transmitter is now initialized.
Notes:
Re-initialization of a transmitter cancels all transmitters already initialized in a system. Therefore, always reinitialize all transmitters for one system (manipulation protection).
All transmitters of one system (up to 4 units) must be initialized within 15 minutes. The ignition must not be switched off within this period.
Manipulation Lockout:
Unauthorized manipulation can result in the IR system being inhibited. The inhibit is canceled once again when the vehicle is opened with the conventional (mechanical) key.