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The Mercedes EIS / ESL Electronic Ignition Switch and Electronic Steering Lock system exists to make sure your car isn’t stolen. Your key has a sequential code, unique to your vehicle, and when inserted into the ignition, your car runs a series of tests, to make sure it’s the right key.
A problem that Mercedes-Benz owners may face is the key no longer turns in the ignition.
This issue is often caused either by a defective key, bad shifter module, a failed Electronic Ignition Switch (EIS) also known as the EIS-EZS or a bad steering lock module (ESL).

EIS
ESL emulator enables you to verify correct functioning of EZS. It works with ignition switches in: W202, W203, W202, W208, W209, W210, W211,W219, W220, W906, W639, and other models.

ESL (same as ELV)
The Engine Control Module (ECM), also called the Engine Control Unit (ECU) or Digital Motor Electronics (DME) ensures that your vehicle operates at optimal performance. The ECM monitors most of the sensors in the engine bay in order to manage your vehicle’s air-fuel mixture and regulate the emission control systems.
It controls a series of actuators on an internal combustion engine to ensure optimal engine performance.
A small plastic card with a magnetic stripe encoded with data.
The user swipe the card in a special reader. If the code is valid the access control system will grant access.
Stripe Card
A small plastic card with a chip built in and encoded with data.
The user waves the card in front of a special reader. As a result, if the code is valid the access control system will grant access. However, if the code is not valid, access will not be granted, and information of this entry attempt will appear in the log.

Proximity Card
A small plastic card with a chip built in and encoded with data.
The user waves the card in front of a special reader. As a result, if the code is valid the access control system will grant access. However, if the code is not valid, the system will not grant access and will log the event.

Proximity Fobs
Door will open automatically in case of power loss.
Door will open automatically in case of power loss.
Door will lock automatically in case of power loss.
Door will lock automatically in case of power loss.
A large electro-magnetic lock together with a strike plate used to lock and un-lock a door. When current is flowing through the electromagnet the magnet attracts the strike plate and the door is locked. When the current flow stops, the electro-magnet is no longer a magnet and the door unlocks. You can find more information and images in our Magnetic Lock – MagLock page.
Maglock and Strike Plate
Electric strike Plate is an access control device, with mechanism containing a motor or a solenoid. When current flows through the motor or the solenoid, it retracts and dis-engages from the strike plate.
When the relay is activated the N.O. tab closes, causes a current flow through the solenoid, the solenoid is activated and the door opens.
You can find more information and images in our Electric Strike page.

Electric Strike Plate
Electronic Lock is an access control device, with mechanism containing a motor or a solenoid. When current flows through the motor or the solenoid, it retracts and dis-engages.
When the relay is activated the N.O. tab closes, causes a current flow through the solenoid, the solenoid is activated and the door opens.

Electric Lock
A technology named after its discoverer, John Wiegand, and used in access control proximity cards and proximity fobs. These cards and fobs contain sets of embedded wires with magnetic properties that are difficult to copy. Access control readers can read the data contained in the set of wires in the proximity cards and proximity fobs, and send it to the access control computer for verification. Once the data is verified, the access control system may activate a relay to open a door or a gate. However, if the data can not be verified, the access control system will not activate the relay.
This protocol has nothing to do with the Wiegand effect described above. The protocol prescribes how to send data read by the proximity reader to the access control system. Typically the data is made of numbers. Wiegand 26 format is very commonly used within access control system. The number 26 means 8 bits for the facility code and 16 bits for the numbers on the card.
A metal bar mounted on a door to provide quick exit by pushing on the bar. This is a mechanical device and is not dependent on electric power, therefore safe to use in emergency situations when the power may be down.
If you would like to learn more about the panic bar, you can find more information and images in our panic bar page.

Panic Bar
Mortise locks require a mortise which is a pocket cut into the door. So, the mortise lock fits inside. In general these locks are more common in commercial buildings, since they are more secure. However, the installation is more difficult than a cylindrical lock.

Mortise Lock
A cylindrical lock is installed through the door with a door knob or a lever on both sides of the door. When turning the door knob or the the lever, the cylindrical lock allows the door to open. This lock is not as secured as a Mortise lock, however, the installation is much easier.
If you wish to read a case study, please visit our post Access Control case study.
Access control system is electronically controlled system which allows access to doors and gates in secured areas.
The access control system uses readers and/or receivers mounted by doors and gates.
In order to gain access, the qualified personnel use a coded key fob, a coded card or a coded transmitter key fob to communicate with the reader or the receiver controlling a lock. Once the reader or the receiver determines the key fob/the card or the transmitter code is valid, the controller will activate a relay which controls the specific door. In addition to opening and closing the door or gate, the access control system also keeps data log with all entries of personnel through each controlled door or gate. Also, it includes in the log unsuccessful entry attempts. Therefore, an administrator can review the log and print it.
A Tele Entry is part of an access control system, which includes a key-pad, a reader and a phone line. As a result, a visitor may use the tele-entry keypad to select a resident and speak to him using the built-in phone. The resident then can allow entry by clicking a digit on his phone.
For more information please visit our Tele Entry page.

A device mounted by a secured door or a gate, it reads electronic data from a card or a fob, and sends the data to the access control computer for evaluation. If the data is valid, the controller will open the door or gate and log the event in a database. An administrator has the option to view the data in real time or future time. However, if the data is not valid, the controller will not open the door or the gate.


A device allowing to control entry. A visitor may enter a code. When the code is valid the access control system will grant access. However, if the code is not valid, the access control will not grant access.

A small plastic card with a magnetic stripe encoded with data.
The user swipe the card in a special reader. If the code is valid the access control system will grant access.

A small plastic card with a chip built in and encoded with data.
The user waves the card in front of a special reader. As a result, if the code is valid the access control system will grant access. However, if the code is not valid, access will not be granted, and information of this entry attempt will appear in the log.

A small plastic card with a chip built in and encoded with data.
The user waves the card in front of a special reader. As a result, if the code is valid the access control system will grant access. However, if the code is not valid, the system will not grant access and will log the event.

Door will open automatically in case of power loss.
Door will open automatically in case of power loss.
Door will lock automatically in case of power loss.
Door will lock automatically in case of power loss.
A large electro-magnetic lock together with a strike plate used to lock and un-lock a door. When current is flowing through the electromagnet the magnet attracts the strike plate and the door is locked. When the current flow stops, the electro-magnet is no longer a magnet and the door unlocks. You can find more information and images in our Magnetic Lock – MagLock page.

Electric strike Plate is an access control device, with mechanism containing a motor or a solenoid. When current flows through the motor or the solenoid, it retracts and dis-engages from the strike plate.
When the relay is activated the N.O. tab closes, causes a current flow through the solenoid, the solenoid is activated and the door opens.
You can find more information and images in our Electric Strike page.

Electronic Lock is an access control device, with mechanism containing a motor or a solenoid. When current flows through the motor or the solenoid, it retracts and dis-engages.
When the relay is activated the N.O. tab closes, causes a current flow through the solenoid, the solenoid is activated and the door opens.



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