Everything about the sound generator (incl. deactivation)

  • The easiest way to mute the sound generator is of course to unplug it. At the same time, however, this is also the most primitive method from a legal point of view. It is more convenient if you can turn it on and off at the touch of a button.

    In PreFaceLift smart ED & EQ from 2017 to the end of 2019, the sound generator can be switched off and on again at the touch of a button. This is no longer possible in the smart EQ facelift from the end of 2019 until the end of production. The button for this is still there, but it can no longer be pressed. However, a button that can be pressed can be retrofitted. To do this, you have to swap the button on the one hand and code it using dt4all on the other so that the smart's sound generator reacts to the push of a button. The item numbers for the button are as follows:

    • 453 905 42 01 (facelift - cannot be pressed)
    • 453 905 41 01 (PreFacelift - pressable)

    If you want to retrofit the pushable button in the facelift, you have to order the button from the pre-facelift from the Mercedes dealer (~ 25 €). You also have to go to "Vehicle Sound for Pedestrian" and find the "VSP_v1a3" control unite. In there you need to set "Activiation by Switch" and "Switch_DTC_Enable" from "absent" to "present".


    At your own risk! For cars in the United Kingdom first registered after July 2019, that's illegal. You can find more on the subject with the help of the term "AVAS", which stands for "Acoustic Vehicle Alerting System".

    If you also want the sound generator to always be switched off and not switched on, you can install an extra module for this. This recognizes the vehicle start and gives an impulse to the lines of the switch as if it had been pressed.

    If the button could already be pressed at the factory, you only have to install the module. If it cannot be pressed, you must at least activate it using dt4all so that the smart would react to the button. Even if you don't swap the button. The module for this is available, for example, in the smart eMotion shop:

    EUR 74.95

    Many thanks to five and the entire smart eMotion community, who worked on the content of this wiki.


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