From the manual
Cycle Completion Signal
The cycle completion signal alerts you when a cycle completes and the dishwasher has washed and dried the dishes. You can choose to disable the tone or adjust the volume.
NOTE: The unit must be powered OFF before activating.
To activate:
• Press and hold the right "Cancel Reset" button then press and hold the ON/OFF button.
• When the light on the "Cancel Reset" button you are pressing illuminates and the tone goes off, release both buttons.
• Press the far right "Cancel Reset" button until you achieve the desired volume or until there is no tone (to turn off).
• Press the ON/OFF button. The setting is now saved.
You're welcome :)