Ok I am going to try and explain what has happened and please excuse my ignorance. 2018 GMC with the 6.2L. I clicked on F3 and then auto detect then read ECM. At that point I screwed up something because it says it cannot accurately determine the internal segment layout for this file. please send file to support. Now I do not know what file and where to get it to send it to you. At this point I am lost at what to do. Please help. Thanks : Eddie