Chapter 4. Testing and Troubleshooting
61200063L1-20
DSU III TDM User Manual
4-27
Table 4-3. Messages from the DSU/CSU
Message
Meaning
Probable
Cause
Action
LOOP IS
NORMAL
Good local loop
signal being
received from the
telco.
Good local loop. No action
required; unit
properly
connected to telco
circuit.
OPEN LOOP
Unit not receiving
a signal from the
telco.
Bad telco cable
from the DSU to
telco jack or bad
circuit to telco.
Replace telco
cable from DSU to
wall jack. If a
problem persists,
contact telco
provider.
NO RX SIGNAL
Unit detects
sealing current but
no data signal
from telco.
Bad conductor in
telco cable from
DSU to telco jack
or bad circuit to
telco.
Replace telco
cable from DSU to
wall jack. If a
problem persists,
contact telco
provider.
OOS/
OOF_FROM NET
Unit detects an
Out of Service or
Out of Frame
condition from the
telco.
Telco is having
problems with
DDS circuit or
remote unit is
turned off or
disconnected.
Check remote
unit. Contact
telco service
provider.
CHECK TELCO
LINE
Transmit/receive
pair reversal
detected.
Telco wall jack
wired incorrectly.
Switch wire pairs
in wall jack or
contact telco
service provider.
TEST FROM
TELCO
Telco activated a
loopback to test
the DDS circuit.
Telco is testing
circuit.
Wait until test is
complete or
contact telco
service provider.
Summary of Contents for 1200063L1
Page 1: ...57 6 CVC 5GTXKEG 7PKV 2CTV 0WODGT 3422285 3 QEWOGPV 0WODGT 83422285 3 42 RTKN 3...
Page 12: ...xii DSU III TDM User Manual 61200063L1 20 Table of Contents Appendix F Glossary F 1 Index 1...
Page 16: ...xvi DSU III TDM User Manual 61200063L1 20 List of Tables...
Page 24: ...Chapter 1 Introduction 1 8 DSU III TDM User Manual 61200063L1 20...
Page 44: ...Chapter 3 Operation 3 14 DSU III TDM User Manual 61200063L1 20...
Page 72: ...Chapter 4 Testing and Troubleshooting 4 28 DSU III TDM User Manual 61200063L1 20...
Page 86: ...Chapter 7 Configuring DTE Options 7 8 DSU III TDM User Manual 61200063L1 20...
Page 90: ...Chapter 8 Configuring Test Options 8 4 DSU III TDM User Manual 61200063L1 20...
Page 108: ...Appendix A Pinouts A 6 DSU III TDM User Manual 61200063L1 20...
Page 112: ...Appendix B Configuration Profiles B 4 DSU III TDM User Manual 61200063L1 20...
Page 114: ...Appendix C DSU to Modem Interconnect C 2 DSU III TDM User Manual 61200063L1 20...
Page 116: ...Appendix D EIA 232 Connector D 2 DSU III TDM User Manual 61200063L1 20...
Page 120: ...Appendix E Specifications Summary E 4 DSU III TDM User Manual 61200063L1 20...
Page 130: ...Appendix F Glossary F 10 DSU III TDM User Manual 61200063L1 20...
Page 136: ...Index 6 DSU III TDM User Manual 61200063L1 20 Index...