I have a 2003 Z4 with an automatic transmission. Recently the transmission warning light remains on after start up. If I go a couple of miles, stop, turn it off, and restart it, the light goes out. The light is only on when the car is cold. When the light is on, the transmission will not shift into any of the "manual" gears. The car has 54000 highway miles. The transmission fluid has not yet been changed. Anyone have any experience with this?