Car sat for 5 days while on vacation now won't start. No power at all.

Hey casey40510, thanks for the response. I thought it was ignition switch only until I realized that the car has no power..no lights, radio, no sounds at all. So, I guess in the meantime the battery went dead or blew a cell. That seems to be a tip-off to the major problem. Thanks.

I would charge or replace the battery, and if the same issues persist, test the ignition switch. Yes, the radio should work with the key off, as there should be a hot at all times power supply, but with an ignition going bad, it could also cause things to stay on, draining the battery. I'm not saying to replace, but testing is a good idea.