3Com 980/000048/001 Modem - Telephone Line Connection

Troubleshooting Guide 3 - 3
Modem - Telephone Line Connection
Connection Problems in Answering a Call
Modem does not receive a dial tone
Attach a t elephone direct to the wall outlet to check i f a dial tone exists.
Make sure the telephone line is connected to the appropriate modem’s
rear panel PSTN jack.
Modem does not go off-hook and answer an incoming call
Check t hat the auto-answer ring count configuration option
(S-Register 0) is set to a value other than 0.
Check t hat the DTE is providing DTR to the modem.
If the DTE does not provide DTR to the modem, check t hat the modem’s
DTR signalling configuration option is set to ignore the state of DTR.
Check t hat all cables are attached to the right connectors at the rear of
the modem.
Modem goes off-hook, answers, but does not connect
Perform a local analogue loop test and check t hat data entered at the
DTE is echoed back to the DTE.
Check t hat the originating modem’s configuration is compatible with
your receiving modem’s configuration.
Check t hat the originating modem recognizes your modem’s answer tone.
Check t hat the originating modem supports your modem’s operating
protocols.
Force your modem to operate using the same transmission protocol as
the originating modem to see if they connect.