200 GMC Jimmy. No crank

[Patrick Duster]

2000 GMC Jimmy,have no crank no start no dash lights obd reader no power.i change the ignition still the same no power.

[riverbanks]

Nothing at all?no horn, headlights?

[Doug_Scott]

Starting at the battery,  check voltage.  Remove both cables, ground cable first, inspect and clean both ends of both cables. You didn't mention it, but, have you tried boosting it? 

Why did you change ignition switch?  That is an odd spot to throw parts in the hopes it is broken.