Panasonic UF-490 - Manual (Page 106)

Troubleshooting
106
If you do not hear a dial tone when the key is pressed or the incoming call does not ring on
your machine (no automatic receive).
Checking the Telephone Line
1 Unplug the Telephone Line Cable from the
telephone jack that was supplied by the
telephone company.
2 Plug a different regular telephone into the
same telephone jack.
3 Check for dial tone through the handset. If
there is still no dial tone, report it to your local
telephone company.
or
Call from another telephone to this number. If
the telephone does not ring, report it to your
local telephone company.
MONITOR