A wired Issue

Wife called me at work and said her daily driver had some issues. She said that she smelt something like hot metal and all her gauges went hay wire. The temp gauge went above the highest mark the AMP gauge went to the lowest point, the gas gauge went to max and the RPM went to zero. The car ran fine no other issues and no check engine light no codes. Well long story short all appeared ok until I turned on the lights and all went as pervious described. Then I turned the cluster dimmer all the way clock wise to full dim and everything went back to normal. When I turned it back counter clockwise all went haywire is it as simple as replacing the headlight switch or is there something more ominous lurking.

Coasty