04 Ram 1500 headlights cut off randomly. Tap das come back on. Replaced main headlight switch and problem persists. What can I do next

 

Is "das" a typo and you mean "gas"? If so, could be bad battery or alternator.
You should check battery voltage at rest, during start, and while engine is running. Check alternator output at battery.
Battery voltage at rest should be at least 12.4V. It should not go below 10V on start, and should be above 13V at minimum while running.
Turn on headlights with truck running and see if you get a drop in voltage.

 

I suspect the OP has fat fingers like I do and meant to type "dash". That would sound like a loose wore or iffy connection at a ground.

 

I am posting this this as an off the wall guess worth considering. Years ago while driving my 2002 Dakota at night my headlights started strobing real fast. At first I thought I was imagining it. The problem kept happening. I did some online research and found a comment about guys having horns and interior lights suddenly turning on. I think the culprit was called a Body Control Module and it was located behind the kick plate panel by the driver's left foot. I ordered that part from an online MOPAR parts place and it installed fast and easy. My problem went away. That part apparently controls all non-engine related electrical functions. Somebody here will know much more about it than I can express.