Your original question was about driving in the rain. You shouldn't touch the DSC button, and that way DSC will always be active, automatically coming into play when it is required.

The confusion comes from those posters who have had trouble on a hill, in deep snow or on ice, when DSC by itself isn't enough to find traction, and then the computer automatically steps in and reduces engine power. By turning off DSC it defeats that second function, allowing more wheel slip than with DSC enabled. The traction control is still enabled (via single-wheel braking) but the throttle is not reduced, so the wheels can spin to allow you to dig out of a snow bank, or chew your way up an icy driveway. It isn't for offroading, but rather for when you want to allow a spinning wheel. It should be used with caution, since the traction control will still apply a single brake (potentially overheating a brake).

Those aren't normal driving situations, and so unless you are stalled on a steep icy hill, and applying throttle doesn't have any effect since the DSC is reducing throttle automatically, you should always leave the DSC button alone. DSC is best left on at all times on the road.

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2007 X3 3.0si, 6 MT, Premium, White

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