I just downgraded successfully from 3.50 to 3.41. I then tried to exit service mode by using Lv2diag.self. It turned off after 10 seconds like it was supposed to, however when i turned it back on it was still in service mode. I have tried redownloading different Lv2diag.self files to make sure it wasn't corrupt, but everytime I try it just does the same thing. I am using the rightmost USB port, and the files are named correctly.