ABS sensor is bad so the ABS light comes on, driving the 4 Wheel drive Light is on

Question

my left front ABS sensor is bad so the ABS light comes on, sometimes the 4 Wheel drive Light comes on and when it does you cant shift the into 4 wheel drive just 2 wheel drive unless the 4wheel light is off , its a Steady on not its not flashing , I have checked all fluids and tire pressure, is this 4 wheel light on condition because of my ABS sensor light is on because I do have an opened sensor . ?