do you have to press the w button to in-gauge the awd
W Winter/Wet driving mode - enhanced vehicle traction (automatic transmission) This mode may be selected for starting/moving off on slippery roads. (Lay mans terms, the car starts out in 2nd gear vs 1st) To answer your question, No. AWD is always activated/available. If the wheel sensors detect any wheel slippage particularly to the rear wheels, then the computer will compensate the wheel spin or add power to the other wheels and help you get traction, but otherwise your car is only using the front wheels for power when it isn't slippery.
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