

An example looks something like this
(It shows an one adapter in the first image but it shows an actual harness further down)
I didn’t see one for Mercedes on that site, but it sounds like it mentions the existence of them here under method 3
Installation usually involves:
• Accessing the wiring behind your start/stop button
• Installing the module inline with the existing harness
• Securing the module in a hidden location
That page also suggests that you may be able to disable it with a programming tool on some models. Depending on what you have I’d give that a try first
Good luck! Report back it you find something that works! I’ve had the privilege of never having a car new enough to include this “feature”