This is crazy but I imagine you could have the 4WD mode if you have a good OBDii scan tool, with mine i remember that I was able to activate the AWD solenoid, which transfers power to the front wheels but the car was stationary, I will check it out next time I service my car.
This means the scan tool will have to be hooked up all the time. Not at all practical but it offers the possibility.
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