ok my 97 range rover with a 4.0 drives goods and shifts like it should, airbags work great but when i put high to go into 4x4 and shift into 4x4 the gear light on my dash comes on, what does that mean? i have never taken my truck offroad since i bought it 3 years ago, but i plan going hunting with some friends soon and might need to use the 4x4.