How can you disable DSC all the way, in other bmw's you can just hold the dsc button until the yellow brake light comes on, but when I hold the DSC button on my car nothing happens, only the 4x4 DSC light comes on?

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2006 BMW X5 4.8is Lemans Blue/Beige/Dark Maple
-Nav, Comfort Seats, Heated Steering Wheel,
Rear Airbags, AUX Input
2009 BMW M3 Space Grey/Black/Carbon
-all options