The instrument panel lights don't work on 1990 Dodge Caravan

They only come on when the light switch is turned all the way to the left...this also turns on the dome lights. What is wrong that they don't light when the van is turned on.

2 answers
the dimmer switch is working but the rheostat in the dimmer switch is done for replace the switch.
Answer #1 would b correct in my opinion. Good job!