Audi A4 Owners & Service Manuals

Audi A4: Unlocking and locking the vehicle

Opening and closing
Fig. 27 Door handle: sensor for locking

Depending on the vehicle equipment, you may have various options for unlocking and locking your vehicle. The settings in the MMI specify which doors will unlock.

Unlocking or locking using the vehicle key buttons

  • To unlock the vehicle, press the button, fig. 26.
  • To lock the vehicle, press the button once.

Unlocking or locking using the sensors

Applies to: vehicles with convenience key

  • To unlock a door or the luggage compartment lid, grasp the door handle or luggage compartment lid handle.
  • To lock the vehicle, close the door and touch the sensor on the door handle once > fig. 27.

    Do not grasp the door handle while locking the vehicle, or else the vehicle will not lock. The door cannot be opened for a brief period directly after locking it. This way you have the opportunity to check if the doors locked correctly.

Unlocking and locking with the Audi connect vehicle control service1)

Applies to: vehicles with Audi connect vehicle control

Requirement: Audi connect vehicle control services must be set up. The vehicle must be parking and the ignition must be switched off.


Observe the safety precautions.


  • Only use the vehicle key when you can see the vehicle.
  • The vehicle can only be locked when the "P" selector lever position is engaged.
  • Do not use the vehicle key to lock and unlock when you are inside the vehicle. Otherwise, you could trigger the anti-theft alarm*. If this happens, press the unlock button.


Applies to: vehicles with convenience key

  • When unlocking or locking the vehicle, the convenience key cannot be more than approximately 4 feet (1.5 m) away from the door handle or luggage compartment.
  • Unlocking with the convenience key (keyless access) can be deactivated in the MMI system.
  • To prevent the vehicle battery from discharging, the energy management gradually switches off convenience functions that are not needed. You then may no longer be able to unlock your vehicle with the sensors.

1) In certain countries.

LED and battery in the vehicle key

Opening and closing
Fig. 28 Vehicle key: removing the battery holder

Opening and closing
Fig. 29 Vehicle key (rear side): removing the battery holder

LED in the vehicle key

The LED (1) indicates the vehicle key function.

  • If you press a button briefly, the LED blinks once.
  • If you press and hold a button (convenience opening/closing), the LED blinks several times.
  • If the LED does not blink, the vehicle key battery is drained. Replace the battery in the vehicle key.

Replacing the vehicle key battery

  • Press the release buttons (2) > fig. 28 and remove the mechanical key.
  • Press the release buttons (3) > fig. 29 while pulling the battery holder out of the vehicle key in the direction of the arrow.
  • Replace the battery and insert the new battery with the "+" symbol facing down.
  • Slide the battery holder carefully into the vehicle key.
  • Insert the mechanical key.

If the indicator light appears with a corresponding message, the vehicle key battery is drained and must be replaced.


If batteries or coin cell batteries are swallowed or enter the body in any other way, they can cause serious or fatal injuries within a short period of time. There is a risk of chemical burns.

  • Keep vehicle keys and key fobs with batteries out of the reach of children.
  • Keep new or used batteries away from children.
  • If the battery compartment on a vehicle key does not close securely, stop using the key and keep it away from children.
  • Seek medical attention immediately if you suspect that a battery was swallowed or has entered the body in any other way.

For the sake of the environment

Batteries and electrical/electronic devices must be disposed of in an environmentally safe manner.


Replacement batteries for the vehicle key must meet the same specifications as the original battery.


     Luggage compartment lid

    General information WARNING Applies to: vehicles with anti-theft alarm system: When the vehicle is locked from the outside, no one, especially children, should remain in the vehicle, because the

     Automatic luggage compartment lid

    Applies to: vehicles with automatic luggage compartment lid Fig. 32 Luggage compartment lid: 1 closing button*, 2 lock button* (vehicles with convenience key*) The luggage compartment lid can be open

     Mechanically unlocking the luggage compartment lid

    Applies to: vehicles with folding backrests Fig. 34 Inner luggage compartment lid: access for emergency release (1) sedan, (2) allroad Applies to: vehicles with fixed backrests Fig. 35 Rear bench


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