Troubleshooting guide

Table Of Contents
365
Status LEDs
DSU PRI and R2 Card LEDs
Three status LEDs and 14 circuit LEDs are mounted on the DSU card
faceplate. Each of the card circuit LEDs shows the status of one circuit.
Table 103: DSU Card Circuit LEDs
LED State Meaning
DSU PRI DSU R2
L0 and L1 right side - solid red error error (no physical
layer is present or
network/line side
(NT/LT) jumper is
not set correctly)
right side - off no error
left side - solid green D-channel
established
AB signaling
established
left side - flashing
green
Layer 1 established
left side - off no link
right side - yellow
with left side -
flashing green
alarm indication from far end
right side - yellow
with left side - off
blue alarm from card - normal during
link startup
ST (status) flashing operational
off not operational
solid card is booting
MS (message
system)
solid green message link open to the system
off message link not open to the system