@ givegodachance !

If your VX is in TOD position rear wheel always lights up,as you drive the front wheels would light up 15%
When the TOD is IN 4LO all lights will turn on because the tranfer case is in LOCK position,so all whell are.

But what i believe is happening to you is that you aren't locking the tranfer case completely and wouldn't light the TOD at all if that is the case.

And remember,ALWAYS change the TOD with the gearbox in "N" position