Cisco 1751 User Manual
Page 55

3-13
Cisco 1751 Router Hardware Installation Guide
78-11258-04
Chapter 3
Troubleshooting
Problem Solving
Table 3-4
Troubleshooting ISDN
WIC
Symptom
Check the Following
Possible Solution(s)
ISDN S/T
Router is on,
but the OK
LED on the
card is off.
Is the OK LED on the
router front panel on?
If no, the router might be
malfunctioning. Contact your Cisco
reseller.
Are all ISDN cables
properly connected?
If yes, the ISDN line might be
malfunctioning. Check with your
ISDN service provider.
Is the NT1 LED on?
If no, the NT1 might be
malfunctioning.
ISDN U
Router is on,
but the NT1
LED on the
card is off.
Is the OK LED on?
If no, the router might be
malfunctioning. Contact your Cisco
reseller.
Are all ISDN cables
properly connected?
If yes, the ISDN line might be
malfunctioning. Check with your
ISDN service provider.
Is the ISDN line
connected to the card
ISDN U port?
If yes, the ISDN line might be
malfunctioning. Check with your
ISDN service provider.