Mercedes-Benz E-Class Quiz
Opening and Closing

Keys. Changing the locking system setting. Emergency key

In this manual: Opening and Closing
Introduction — 5At a glance — 6Safety — 25Opening and Closing — 17Seats, steering wheel and mirrors — 12Lights and windshield wipers — 11Climate Control — 11Driving and parking — 44On-board computer and displays — 29Stowing and Useful Information. Good to Know — 1Stowing and Useful Information. Storage Options — 10Stowage and convenience features. Convenience features — 7Maintenance and care — 11Roadside assistance — 13Wheels and tires — 13Technical data — 13
~3min read

With the Mercedes E-Class (4th gen. W212, 2009–2016), you can adapt the locking logic to suit your driving style. This article explains clearly how to change settings or use the emergency key deliberately in exceptional situations, so you always stay flexible.

Changing the locking system setting

You can change the locking system setting. Then, when the vehicle is unlocked, only the driver's door and the fuel filler flap are unlocked. This can be useful if you often drive alone.

Changing the setting: Press and hold the buttons simultaneously for about six secondsandon the key until the battery indicator lamp flashes twice.

Info

If the locking system setting is changed within the vehicle's reception range, pressing the buttonoraccordingly
  • to lock or
  • to unlock the vehicle.

The key now works as follows:

Unlocking the driver's door: Press the button oncepress.

Central unlocking: Press the button twicepress.

Lock centrally: Press the buttonpress.

With KEYLESS-GO, the function changes as follows:

Unlocking the driver's door: Touch the inside surface of the driver's door handle.

Central unlocking: Touch the inside surface of the door handle of the front passenger door or the rear doors.

Central locking: Touch the outer sensor surface on one of the door handles.

Restoring factory settings: Press and hold the buttons simultaneously for about six secondsanduntil the battery indicator lamp flashes twice.

Emergency key

General Notes

If the vehicle cannot be locked or unlocked with the key, use the emergency key.

If you unlock and open the driver's door or the trunk lid/tailgate with the emergency key, this triggers the intrusion alarm system.

You have four ways to stop the alarm:

End alarm with key: Press the buttonorof the key.

or

Insert the key into the ignition lock.

or

Stopping the alarm with KEYLESS-GO: Press the START/STOP button in the ignition lock. The key must be inside the vehicle.

or

Locking or unlocking the vehicle with KEYLESS-GO. The key must be outside the vehicle.

If you unlock the vehicle with the emergency key, the fuel filler flap is not unlocked automatically.

Unlocking the fuel filler flap: Insert the key into the ignition lock.

Removing the emergency key

Notschlüssel entnehmen

Slide the release slidein the direction of the arrow and at the same time pull the emergency keycompletely out of the key.

Further information on:
  • Unlocking the driver's door
  • Unlocking the trunk
  • Unlocking the tailgate
  • Locking the Vehicle

Inserting the emergency key

The emergency keyfully into the key until it engages and the release slideis back in its basic position.

The locking system setting options of the Mercedes E-Class W212 (model years 2009–2016) provide added security, especially when you often drive alone. Functions such as opening only the driver's door or using the emergency key increase protection against unauthorized access.

These well-considered details underline the high standard of everyday practicality and security that the E-Class BR 212 offers. This makes the model a reliable companion in any situation.

Question: When should you change the locking system setting?

Answer: When you often drive alone and want to open only the driver's door to increase security.

Question: What is the advantage of the emergency key?

Answer: It allows you to lock and unlock the vehicle mechanically if the key battery is empty or the electronics malfunction.

Test yourself

A quick Mercedes-Benz E-Class quiz: every answer comes with an explanation and a link to the manual page.