Rear pinion bearing went out swapped rearends. Ran battery dead with the radio. Started with jump pak now the alternator is over charging and motor misses and won't take fuel. I've swapped alternators checked wires. With meter on battery and jeep running the voltage slowly climes. Got to 20v before i shut it off. Checked continuity on the feild wires the ground is good with pcm plugged in but not when the pcm is unplugged and negative battery disconnected. Everything I've read points to pcm being bad. Hoping for some advice before jumping to new pcm.

 

Did you get the jumpers hook up on the wrong terminals?

 

No I didn't
also add I've checked all fuses under the hood.

 

Voltage that high will likely make it run in limp mode or not well at all. But if the alternator checks out OK, then the ECM is not working right