Pulling my hair out here.... 99XJ 4.0- Have the classic no voltage gauge and fuel gauge along with no start. Stays the same with Cam,Crank,Map,TPS unplugged. Im only getting 3v reference to the sensors as well. Will not communicate with scan tool as well. Previous owner has changed PCM twice and says that it runs for a few days then dies with same symptoms again. I have a pcm to swap in but am worried that it will end up fried again. Any suggestions on what could be killing PCMs in this thing? What circuits could possibly cause this?