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How to Unlock the Automatic Gearbox on a Smart Fourfour

Model: Smart Smart 453 - Years: 2014, 2015, 2016, 2017, 2018, 2019, 2020, 2021, 2022
Part: Transmission

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Video tutorial

Unlocking the automatic gearbox on a 2019 Smart Fourfour is a fairly simple operation to perform yourself. To unlock the gearbox, you need to remove the lower plastic cover of the gearbox mechanism to access the internal lever and the yellow connector.

You have two options: the first is to manipulate the internal lever mechanism by pulling it down and letting it lift; usually, performing this operation will unlock the gearbox. Alternatively, you can disconnect the yellow connector and, before reinserting it, move the lever.

If, despite correctly performing both options, the gearbox does not work, you will need to call a recovery vehicle to take the car to a workshop for a diagnostic check.


Posted on 6 June 2026 by ScegliAuto


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by ScegliAuto

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