Headlight problem

95 Ranger XL pickup truck headlights work only on low beam. When I select highbeam I only have daytime running lights and also no highbeam indicator. Someone told me it was the daytime running lamp module. Is there a way to verify this diagnosis? I checked the headlamp bulbs and they are ok. Checked the power coming out of the dimmer/multifunction switch and it is ok.

When you "brighten" your lights, does your instrument panel go dark or otherwise change brightness?