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4 Troubleshooting
4.5 The “D Channel” LED is not lit.
Cause:
The AVM ISDN-Controller T1/T1-B cannot establish
a D-channel connection.
Possible remedies:
- First check whether the “Sync” LED is lit. If not,
proceed with the instructions under Section 4.4,
“The ‘Sync’ LED is not lit”, above.
- Make sure your ISDN provider has activated the S
2M
interface.
- Check whether the correct D-channel protocol was
selected during the driver software installation. To
change the D-channel protocol you do not need to
repeat the entire software installation. In DOS, change
to the directory containing the desired T1 protocol
software file (1TR6 or DSS1) and copy the T1-base.t4
file found there to the directory where the driver
software was installed. In Windows NT or Novell
NetWare, use the Setup program.
- Check the cable from the AVM ISDN-Controller
T1/T1-B to the NT. It must be grounded to the NT,
and secured to the AVM ISDN-Controller T1/T1-
B by tightening the finger screws on the sub-D
connector. Do not use extension cables for this
connection.