I have a BMW X3 M 08, with 140,000 miles, new motor, trans, and now starter. It won’t start, but there is 12.5 v of power in the battery before starting. I’ve tried to jump it with another car, etc, and it did not work. When I go to start it, all the lights come on, and then it clicks, but does not start. Also, there is no cranking. Checked the ground cable, all the fuses, including the relay starter cable, and the connection cable to the starter. Everything is good and has power. Anti theft is not on, I believe, since there is no light on. It may be the key, but it was working 100% before it broke down. Any suggestions on what it could be?