Let the shop fix it, but be aware that a common cause of both the 4x4 and ABS lights being on (given that they are two separate systems) is a failure of a wheel speed sensor or the wiring to the sensor. Both systems rely on the signal from each wheel speed sensor. Checking the codes will tell them if a sensor is out, and which one.

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2007 X3 3.0si, 6 MT, Premium, White

Retired:
2008 535i, 6 MT, M Sport, Premium, Space Grey
2003 X5 3.0 Steptronic, Premium, Titanium Silver
2002 325xi 5 MT, Steel Grey
2004 Z4 3.0 Premium, Sport, SMG, Maldives Blue