Motorola 920/930

The 54# Tip:
Type 1#, 2#........54# on the keypad (when you're not in the menu) to get the phone number used for with this key when speed dialing.

Keyboard lock
if you push * and # on the same time your keyboard locked. When you press it again, you unlock your keyboard.

Supplementary Menu
If your Motorola CD920 or 930 has the engineering software, you can get an engineering mode by typing : ***113*1*, but you have to maintain each * during 3 sec to get a square. So 3 squares, 113, 1 square, 1, 1 square, CALL.
If the software is present you have one supplementary menu. To remove it typ ***113*0* like above.

To put the counter to 0 even global counter, just do a reset factory in the Config menu.