How do I use the Control Lock feature to prevent unintended use?

To turn on Control Lock, press and hold the Heated Dry button for at least 3 seconds. To turn it off, press and hold Heated Dry again for at least 3 seconds. When Control Lock is active, all buttons are disabled and the light will flash 5 times if any pad is pressed, though the dishwasher door can still be opened. (Page 6)