dashboard lights question!

[Roeid]

I have a 2001 limited edition 4runner 190 000km. In the dashboard, i noticed the 4 wheels were on, but not the circle in the middle (like when i switch to 4x4). Im trying to find the reason can anyone help?!

And does anyone have a link to dashboard lights detailed for dummies?!

 

[White 4x4runner]

Look to the right of your steering wheel. There should be a button you can push in 4 wheel. That will make the center light light upm orange. It's for the center diff lock. Makes power go 50/50 front and rear. Not too good for pavement.