Cisco 2600 Series Operation Manual page 88

1-Port and 2-Port Channelized T1/ISDN PRI with CSU Network Modules
Figure 8-10
CT1/PRI CSU LEDs
cT1
CSU
CT1/PRI CSU LEDs
All network modules have an enable (EN) LED. This LED indicates that the module has
passed its self-tests and is available to the router.
All PRI modules display four additional LEDs for each port. These LEDs are described in
Table 8-2.
Table 8-2
LED
REMOTE ALARM
LOCAL ALARM
LOOPBACK
CARRIER DETECT
8-8 Cisco Network Modules Hardware Installation Guide
2-Port CT1/PRI CSU Network Module LEDs
RX TX RX
OUT IN MON
ISDN PRI Network Module LEDs
Meaning
Local alarm at remote end of connection
Loss of signal, loss of frame, or unavailability
because of excessive errors
Controller local loopback
Carrier received on telco link
CTRLR 1
EN
CTRLR 0