Recently bought a Crossfire a couple weeks ago, where nothing was wrong with the car at first. Then one day driving back from a lunch the box that shows what gear you are in (I have an automatic so it just said “D”) turned into a black box. It then wouldn’t get out of first gear so I pulled over and turned the car off, only for it to not turn on again. I went to auto zone to get the battery tested, battery was dead - completely. Replaced the battery, car started but black box of death was still there, but I just drove it home in first gear. I then resoldered the RCM and it the black box was gone for a few days. It just came back today after a 5 minute drive, and the car then wouldn’t start or turn over once again so I don’t know what’s going on with that at all. I’m currently going to resolder the entire rcm and not just the 3 notorious connections at the top left. Any ideas on what the issue may be?