When a call is made, the monitor remains off.

Check the monitor power supply on terminals 5 and 6, check that the monitor rings for calls from the outdoor station or check that the power supply generates the call tone: connect a 50-100 ohm speaker between terminals 6 and 8 of the monitor and make a call from the outdoor station. If you have installed monitors that turn on simultaneously with the same call, use an Elvox call repeater part no. 934 after the third monitor and for the next four.