Actually I figured out the solution. Just take the tray that holds the batteries out of the key and then place them both anywhere in car, obviously where it would be difficult for a thief to find them.
The lock will not open if the key is inside the car, when the car has Keyless Go. At least that is how it works on the E-class (I have had one and tried it out several times).
Otherwise it would be impossible to lock the car when driving trough an unsafe part of town (not really a problem where I live unless you consider elks and santa as treaths[:)]).
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MB Viking.
2006 ML 63 AMG arrived! Whooowww!
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