Sometimes when my cell phone is on charge in my 2007 BMW Z4 before I start it, nothing happens when I turn the key. The car is acting like it would if I did not have the clutch pushed in - the key turns, but it doesn't even try to crank. It happens fairly often when the phone is on charge, but not always. I've literally tried to start the car 5 times, then unplugged my phone, tried again, and it always starts.
My guess is that it is somehow causing interference or diverting power that is meant for a device critical to the starting of the car. Any ideas where to start looking?
I also had my battery checked, as it is most likely the original battery in the car. My mechanic said the battery was still in great shape.