Canon i-SENSYS MF4300dn Service Manual page 173

Character Operation button
I [+] key
J [-] key
One-touch dial key test
When the OK button is pushed, it becomes an one-touch dial key test.
The a thorough h characters corresponding to One-touch01 through 08 key are displayed. The character corresponding to respectively disappears when
an one-touch key is pushed. Check that all characters disappear after all one-touch keys are pressed.
Character Operation button
T [Coded Dial] key
U [Redial/Pause] key
Character Operation button
Chapter 14
14-17