HELP PLEASE !!

I am completely stumped and need some fellow jeep knowledge.

I have a 2000 xj that has been giving me the run around with issues. The most recent was I was stopped idling for about 10 min when my check engine light went off and the check guages light came on. I realized the volt guage was completely maxed out at 19 and the oil pressure guage was at around 10.

Started driving got to my destination turned the jeep off and when I got back, turned key to start and no crank. All power is on radio, light on dash, lights in jeep but no movement to start. After attempting awhile thinking it was the NSS I noticed the the odo said "no bus".

Towed home, I still replaced the NSS but nothing. I turned the jeep to accessories and tried to short the starter to see if I could get to crank but wouldn't even throw sparks.

I have no idea what to do, does anyone have any ideas what this could be??? Bad Ecu?

 

Update: cleaned terminals
After cleaning negative nothing happened
but after cleaning positive tried starting and could hear a click but no turn. Tried screwdriver between terminals on starter got a spark then went back to the way it was.

Any ideas?

 

Could be a few things

Start at the beginning, whats the voltage across battery terminals, starter motor terminals, does it get 12V at solenoid from ignition switch ?

Download FSM, search archives, google or youtube "no crank no start etc etc"

 

I was thinking it could be battery terminals or wire, used a voltage meter and got 12.3 v off battery. Weird thing is tried to run codes off it but the old does not seem to have power. Tried 2 different code readers and neither would show anything on display.

 

I was thinking it could be battery terminals or wire, used a voltage meter and got 12.3 v off battery. Weird thing is tried to run codes off it but the old does not seem to have power. Tried 2 different code readers and neither would show anything on display.