BMW Keys and Keyfob History, Security and Evolution

BMW Keys and Keyfob History, Security and Evolution

BMW Ignition Key Code

BMWs built prior to Jan 94 production were equipped with a basic security system in which the user could input a starter immobilizer code when exiting the vehicle.  In order to start the vehicle again, the driver would be required to enter this programmed code before turning the ignition.  Keys for these older BMWs are standard keys and can be cut by any locksmith. 

However starting with Jan 94 Production BMWs, all new BMW were equipped with keys which included an Electronic Immobiliser function linked to a computer chip in each key.  This chip corresponds to a specific code stored in the computer security module of you BMW.  The electronic immobiliser prevents unauthorized entry into your BMW and prevents it being started, unless your correct BMW genuine key is inserted into the ignition and confirmed by the security module.  The original Security modules were known as EWS modules, and evolved over the years.  The EWS system includes a receiver ring located around the key slot that wirelessly reads the chip inside your key.  The key codes are only able to be programmed into new keys by specific BMW Key Centers around the world.  Genuine BMW Keys are only available via the BMW dealer network including directly from the Bimmernav Website.   


The electronic immobiliser secures your car using a chip with an electronic code integrated in the car key. This code consists of a permanent personal code and a second code changed by the immobiliser each time you start the engine.
Whenever the ignition is switched on, the immobiliser first reads the personal code and then asks for the changing code. If both answers are correct, the immobiliser will send another coded signal to the Digital Motor Electronics (DME) to unlock the engine. Without which the engine cannot be started - not even by short-circuiting it.
This data is transmitted wirelessly via an aerial in the steering wheel lock and the key with integrated remote control. The key is equipped with a maintenance-free battery which recharges automatically while driving. 

BMW has a sophisticated computerized security system for starting your car, with the codes securely stored ONLY at the BMW Key Centers. The key is unique to the car and is recognized by the system as genuine.  Any locksmith offering cheap "Non-Genuine BMW keys" will require hacking your internal EWS module in the car erasing the stored key codes and typically removing the ability for you to ever order Genuine BMW keys again!  So the moment you go to a local locksmith to hack your computer with a "Non-Genuine BMW Key", he ends up damaging the system and probably your car computer as well. BMW EWS modules can be replaced, but it is quite expensive to do so, and that is a risk you would be ill advised to take. It is important to take measures that may be costly and time-consuming at the onset than go for cheap, quick fix solutions that will leave you with insurmountable problems later.  Our keys are genuine BMW parts laser cut and coded by BMW, ordered directly from the BMW Key center and are based exclusively on the VIN number of your car.

The BMW Diamond Head Keys are the final version BMW physical metal keys before the introduction of the BMW Keyfobs, which are a fully computerized ignition system

The Genuine BMW Diamond Head Keys are available on our website


  BMW Key Initiation Function

BMW Keyfobs

The Keyfob was first developed by Siemens in 1995 and initially adopted by Mercedes and then eventually by BMW starting with the BMW E65 7 Series.  The keyfob is a plastic key with internal electronics to be used in place of the traditional metal key. Electronics that control locking systems and the ignitions made it possible to replace the traditional key with a sophisticated computerized Key.

Genuine BMW Replacement KeyFob

Comfort access system

The comfort access system was an available option in many of the BMW E series cars. The Comfort Access System uses wireless proximity sensors to put an end to searching for car keys in your handbag or pockets. Simply approach your BMW, open the door and press the Start button. Your unique key is recognised remotely by the comfort access sensors.

As soon as you come within 1.5 metres of your BMW, the comfort access system remotely senses your BMW key, wherever you happen to be carrying it – in your jacket pocket, handbag or briefcase. Simply touch the door handle and the door unlocks. The system also senses when you've entered the cabin and enables the Start/Stop button, so all you need to do is press it and drive off.

And when you reach your destination, your BMW locks all doors automatically simply with a press on the exterior door handle. Your vehicle key also functions as a remote control for opening and closing the tailgate. If you wish, you can store your individual driver settings by using the key's memory function. Up to eleven individual preferences for seat adjustments, exterior mirrors, steering wheel position, BMW Head-Up Display and the audio system can, depending on the model of your BMW, be saved on the key and activated each time you enter your vehicle.

Contactless opening of the tailgate is another innovative technology from BMW ConnectedDrive. A sensor detects a brief movement of your foot below the rear bumper and sends a signal to the on-board computer, which unlocks the tailgate. The tailgate then springs open on its own or is opened by the optional tailgate lift. Contactless opening of the tailgate requires the vehicle system to recognise your car key and unlock the vehicle.

The F Series Keys are the latest version Keys available from BMW.  The F Series keys are the latest version Keys from BMW and incorporate a the most technically advanced computerized key security system available today. 

BMW F Series Keyfob

In many F Series cars there is no longer an insertion slot for keyfobs.  The vehicle can be started without a key as standard.  This function is called "Passive Go" drive authorization.  However to gain access to the vehicle, it is still necessary to have the keyfob within the vehicle.  Starting with the F30, BMWs no longer have a CAS bus in the vehicle as it is replaced by the PT-CAN and FlexRay.

The Functions of the F Series keyfob are:

  • Comfort Access
  • Central Locking
  • Power Windows/sunroof
  • Electronic immobilizer

BMW Comfort Access wiring diagramBMW Comfort Access Wiring diagramBMW Comfort Access Wiring diagram

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