The command modem won't answer.

Make sure that switch number 4 on the bank of 8 is in the up position.
Verify that the firmware is 3.12 or greater. Version 3.12 introduced a method of initializing the command modem with the parameters " AT&FS0=1&D2&W " issued to the command modem&command port at 2400 bps on every reset of the mux. Before version 3.12 you will have to initialize the command modem with a terminal on the command port, by entering the following commands at 2400 bps : AT#MA1 ( result code " Command Modem Access On " ), enter the init string AT&FS0=1&D2&W , AT#MA0 ( result code " Command Modem Access off " ) .