2003 Bounder dash and instrument lights

I suspect that you have something that is ALSO wired in to the light circuit that is causing your problem. I added a couple of extra lights to my interior and I piggy backed in to the circuit that also supplied power to the dash lights. The dash lights would work fine until I turned on one of the new lights, then they would go off, as well as my gauges. Once I moved the new wires to another circuit the problem went away.
I'm guessing that your ICC lights are hooked in to the same circuit with your dash lights. They need to be moved to another circuit.