Hi SteveThis will be the SOS call system, unsure how it will work exactly in the Grenadier but in every BMW if an accident occurs it will automatically call you in the car to see if you need emergency services.
If you don't answer them back then they will automatically inform emergency services of your location so they can respond.
You can press the button manually to call yourself.
The tracking side of things will only be transmitted once pressed or activated via an accident. This is how it works on a BMW, as I say not sure if it's the same in the Grenadier but I can't see it being massively different.