Wife just came back in and couldn't start. Turn key to start complete darkness, no power anywhere.

I did move the shift handle thinking is the NSS and I did get a start. The back up lights have taken a wiggle of the shift lever to get them to come on. Does NSS give a complete now power situation when it's bad/going bad?

Where is the starter relay located on a 98 Cherokee? Is there another relay I can swap out for testing?