Dim mode
With dim mode preset to on, your parent unit display will dim to conserve energy after 10 minutes of inactivity, in which there is neither key pressed nor alert received from the baby unit

NOTES
- If you do not want LCD to dim automatically, turn off the Dim Mode.
Read more: https://manuals.plus/vtech/baby-monitor-manual-5#ixzz7qdWeGhsY