How to get a Mercedes Benz replacement key?

This blog will explain how to get a replacement key for your Mercedes Benz car. This blog will also provide answers to the following questions: what is the cost of a Mercedes Benz replacement key? Should you get a replacement key or an additional key?

How to get a Mercedes Benz replacement key?

A Mercedes Benz replacement key can be ordered from any authorised dealership. Following is the process to get a Mercedes Benz replacement key:

Document verification

Identification of the key tracks

Registration of vehicle in Database

Programming of the replacement key

Teach in the replacement key

Let’s take a look at each step in detail:

Document verification

Customers are required to verify the documents of the vehicle. These documents must prove that the vehicle belongs to them. The dealership can ask for documents like customers driving licences, vehicle insurance and vehicle registration details.

This step is crucial for placing an order for a replacement key. Without correct documents and an undertaking later from the customer it is not possible to order the replacement key.

If the vehicle is the latest, then dealerships keep a stock of un-programmed keys. These keys can be programmed to work as replacement keys. DAS 4 has significantly reduced the overall time to get a replacement key for the car.

Identification of Key tracks.

Mercedes Benz cars have 8 different key tracks, from the factory two keys are already assigned to track 1 and track 2. Once the vehicle reports to the workshop for a replacement key. It is necessary to identify the last or second last used key track.

Based on the key track used, the replacement key is programmed on the same key track. This replacement key gets assigned to segment 2 for the same key track; there are three segments per track.

So for one original key of a Mercedes Benz car, two replacement keys can be programmed. In case, the customer loses both the replacement keys then the entire key track becomes inoperative.

The drive authorization codes are transferred to the replacement key and the number of codes available in each segment is different. Segment 1 has the maximum number of codes and as a replacement key is programmed.

Registration of the vehicle in the database.

The vehicle must be present in the workshop for this step. When a Mercedes Benz diagnosis tool is connected to the vehicle, it can complete the registration process and access the central vehicle database for the programming of the replacement key.

This step is not required for the vehicle with drive authorization system 3 and older. For the DAS 3 and old generation cars, the key can be programmed without the presence of the vehicle in an authorised dealership.

The DAS replacement 3 keys can also be programmed in a device called a keystation, it can read and write new key track and segment data directly into a blank key. 

Programming the replacement key

This step is important as the drive authorization codes are benign transferred from the electronic ignition lock to the replacement key. The total programming time is more than the time required to programme an additional key.

Once the programming is completed, the diagnosis tool can be removed from the vehicle and the key is turned to position 2 to check if the ignition is ON. 

What is the cost of a Mercedes Benz replacement key?

The cost of a Mercedes Benz replacement key is 200 to 250 USD without the mechanical key. The cost can increase to up to 500 USD if the vehicle has a keyless go system. Mechanical keys cost 100 to 150 USD. 

The latest Mercedes Benz cars with the fourth generation of the drive authorization system require programming for the replacement key. Therefore the dealerships can charge up to 100 USD to program the replacement key.

Should you get a replacement key or an additional key?

You should get a replacement key only when you are 100 percent certain the original key is lost or completely inoperative. When the replacement key is programmed the original key will be permanently inoperative.

There is no way to make the original key work again if its replacement key has already been programmed. This is done to prevent unauthorised access to the vehicle. 

If you are not sure or need more time to locate the original key, then getting an additional key is a good option. An additional key is programmed on a different track instead of the last key track used.

This keeps the original key operational and the vehicle will get three function keys. Mercedes Benz dealerships can block a key track temporarily, the key track can be opened again when the original key is found.

Locking and unlocking of the key tracks are only available in the latest generation of the drive authorization system. In the previous generation of the drive authorizations system; it was only possible to lock a key track temporarily.

To unlock a key track in the third generation of the drive authorization system, a special workshop key is required. The workshop key contains the required data to unlock the key track, it is directly inserted into the electronic ignition key of the vehicle.

If all the lights come on, the vehicle can then be started with the replacement key. After this, the original key that is lost or inoperative will be permanently disabled.

Teach – in of the replacement key.

The teach-in process of the replacement key depends on the type of the key. It is carried out only once. In the third and fourth generation of drive authorization system replacement key teach-in process is simple.

The replacement key is inserted in the electronic ignition lock, and the key initialising message appears in the instrument cluster. Once the message disappears, the teach-in process is over.

For replacement keys older than drive authorization generation 3, the key fog is first used to lock and unlock the car. After entering the car, point the key fob towards the inside rear view mirror for a few seconds, the red and green LED lights will blink. The replacement key is ready to use when the green LED light comes on.

Mechanical replacement keys are directly cut from the factory. All the information related to the mechanical key is stored securely in a centralised database. Mechanical replacement Key can also be made from any Key maker. It is only used to gain access to the vehicle, to start and drive it digital key fob is necessary.

Other articles about Mercedes Benz you may be interested in

How many miles can a Mercedes Benz GL450 last?

What makes the Mercedes Benz G Class so reliable?

How do you complete a Mercedes drive cycle?


This blog explained the procedure to get a replacement key from an authorised Mercedes Benz dealership. Due to the latest drive authorization systems, it is not possible to program a blank key fob. The mechanical key can always be ordered directly and does not require any cutting.