If one of the locks doesn't work, you're gonna have to replace it. Wear due to the many uses is the cause and will occur at some point on all Volkswagens.
At the time, you could buy a new lock from the Volkswagen dealer using the lock number while keeping your existing key. Unfortunately, this is no longer possible, but there is another possibility to limit the number of keys.
With the lock set mentioned here you replace several parts that can all be operated with one key.
Are delivered as a set with additional equal keys, but without seals, order them if necessary (see options tab).
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