From the Easy to read site:
Easier to Read BCT15-X Scanner Manual
Scanner Reset: to initialize the scanner's memory, turn off the scanner. Then press 2, 9, and Hold while turning it on (remember the game called Twister?). The scanner will give you the option 'Restore Pre-program List? "Yes"=E / No="."', if you press 'E/Yes', the scanner reloads the pre-programmed systems.
Important! This deletes all programmed data.