MultiModemUSB User Guide

Introduction

Your MT4X56USB was thoroughly tested at the factory before it was shipped. If you are unable to make a successful connection with one of the V.90 modem ports, or if you experience data loss or garbled characters during your connection, it is possible that a particular modem is defective.

However, it is more likely that the source of your problem lies elsewhere. The following symptoms are typical of problems you might encounter:

None of the LEDs light when the unit is on.

The unit does not respond to commands.

The unit dials but is unable to make a connection.

The unit disconnects while online.

The unit cannot connect when answering.

The unit doesn’t work with Caller ID.

Fax and data software can’t run at the same time.

If you experience problems, please check the following possibilities before calling Technical Support (Refer to Chapter 8).

None of the Indicators Light

When you plug in the MT4X56USB, the Power LED should light. After the operating system detects and configures the MT4X56USB, all four TR LEDs should light.

If the Power LED does not light, double-check the cable connections.

If none of the TR LEDs light, check to see that the software from the installation disk has been installed (Refer to Chapter 3).

The Modem Does Not Respond to Commands

Make sure you are issuing the modem commands from the data communications software, either manually in terminal mode or automatically by configuring the software. (You cannot send commands to the modem from the DOS prompt.)

Make sure you are in terminal mode in your data communications program, then type AT and press ENTER. If you get an OK response, your connections are good and the problem likely is in the connection setup in your communications software.

Try resetting your modems by unplugging the USB cable from the MT4X56USB, and then plugging it back in.

Try rebooting the computer.

An MT4X56USB modem might be defective. If you have another Multi-Tech modem, try swapping modems. If the problem goes away, the first modem is possibly defective. Call Tech Support for assistance (see Chapter 8).

The Modem Dials But Cannot Connect

There can be several reasons the V.90 modem fails to make a connection. Possibilities include:

lack of a physical connection to the telephone line

a wrong dial tone

a busy signal

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MT4X56USB

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Multi-Tech Systems MT4X56USB manual None of the Indicators Light, Modem Does Not Respond to Commands