I have had no issues then today I get I. Turn the key and within 2 seconds everything blanked out. No power no dash lights nothing and my battery is good I checked every fuse for continuity then thought it must be the ignition switch relay, changed that out and still nothing but even if that was bad I should be able to turn on headlights etc I would think, I have no idea what else it could be if anyone can help. Please do.

 

look for corrosion on both ends of your battery cables and the engine ground straps

 

Let's back up and start at the beginning.
Have you recently done any work or add ons?
Here are some thoughts....
1. Battery Internal damage
2. Ground strap too block/frame
3. Red power wire to starter
4. Maxi fuses
5. Fuse box failure
6. Starter internal short

 

If you are still trying to use the Crappy Azzed OEM Battery Terminal Connectors, then they are anything but fine. First Mod to do to every H3/H3T is to replace the Battery Terminal Connectors with a quality aftermarket set like Stingers or your favorite brand.

Are we to assume you are talking about and H3? Year and Miles?

What is the voltage of your battery at rest?