Once the Stop Watch is running, an instant press of the mode button should not work to go to the next mode. You have to press and hold the mode button to go back to time screen. There are only 2 ways to get out of Stop Watch: 1. Press and hold mode to go back to Time Screen or 2. 30 minutes of no activity when the Stop Watch is not running, it will go back to the Time screen. If you clear the Stop Watch, it still remains on the Stop Watch screen.