In order to reset your fourth-generation MRX, 540/740/1140, or AVM 70/90 please use the steps below.
Please note before performing the reset, that all settings will be erased.
The unit will be reset to its factory settings.
MASTER RESET
1. With the unit OFF
2. HOLD down the Menu button on the front panel, then press the POWER button on the front panel.
3. Wait until the unit powers up.
4. Once SYSTEM RESET is displayed on the front display, let go of the Menu/POWER button.
5. Power on the unit