PCM not communicating with TCM

I have taken the van to 2 shops and they both tell me that the computers wont communicate to give a fault code from trans. I have changed the output speed sensor. What it is doing is this, Wont shift gears, speedo not working/gas gauge not working. When I do the dash codes it says 2, 23, 55 cannot find anything about the 2 and 23 says something about a manifold pressure switch or something, 55 I know is the end code. The first time the van did this none of the gauges worked or the shifting, I got it home in 'Limp Mode' the next day I went out to look at it and found a 10A gauge fuse was blown, I replaced it and it worked fine all gauges back and was shifting fine. Drove it one day about 40miles the next day went back into 'limp mode' all gauges but speedo and gas working, obviously checked fuse, it was good, swapped it anyways still no-go, so now I cannot figure out why the computers wont communicate and why it wont shift or speedo work. After I changed the output sensor speedo worked for about 10minutes and stopped again, but still would not shift. Also the radiator fans are not working unless I hardwire them to battery. The tranny shop replaced a computer in the van but it did not help. I also noticed a ground wire over by the a/c compressor that was broken, I wedged it back under the clip, dont know what the ground was for or if I even have a good connection on it, dont know how long it was off either. The speedo/trans issue happened out of the blue, I drove it about 20miles came out 2 hours later and it was like that, ran fine when I got there. I dont think I forgot to mention anything.