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CHAPTER 12: Testing and Troubleshooting
NOTE
The Status menu must be selected in order for the unit to display status
messages. Pressing Quick returns to the Main menu, where STATUS
can be selected.
Table 12-1. Messages from the DSU/CSU
Message
Meaning
Probable Cause
Action
Loop is normal
Ground local loop
Indicates good
No action required; unit
signal being received
local loop.
properly connected to
from the telco.
telco circuit.
Open loop
Unit not receiving a
Bad telco cable Replace telco cable
signal from the telco.
from the DSU to from DSU to wall jack.
telco jack or bad If a problem persists,
circuit to telco.
contact telco provider.
No RX signal
Unit detects sealing
Bad conductor
Replace telco cable
current but no data
in telco cable
from DSU to wall jack.
signal from telco.
from DSU to
If a problem persists,
telco jack or bad contact telco provider.
circuit to telco.
OOS/OOF
Unit detects an out-of- Telco is having
Check remote unit.
from net
service or out-of-frame problems with
Contact telco service
condition from the
DDS circuit or
provider.
telco.
remote unit is
turned off or
disconnected.
Check Telco line
Transmit/receive pair
Telco wall jack
Switch wire pairs in wall
reversal detected.
wired incorrectly. jack or contact telco
service provider.
Test from Telco
Telco activated a
Telco is testing
Wait until test is
loopback to test
circuit.
complete or contact
the DDS circuit.
telco service provider.