User Manual

ADCP-75-136 • Issue 1 • November 2002
Page 48
© 2002, ADC Telecommunications, Inc.
Table 14. System Fault Isolation and Troubleshooting Guidelines
Alarm Type LED LED COLOR
None All Normal
Problem: Loss of phone service from one DRU. Service normal at all other DRU’s.
POSSIBLE CAUSE CORRECTIVE ACTION/COMMENTS
1. DRU antenna cable disconnected.
2. DRU antenna obstructed or misdirected.
3. DRU antenna faulty.
4. DRU faulty.
1. Re-connect DRU antenna cable to DRU.
2. Remove antenna obstruction or re-orient antenna.
3. Replace antenna.
4. Replace DRU.
Alarm Type LED LED COLOR
None All Normal
Problem: Loss of phone service from all DRU’s.
POSSIBLE CAUSE CORRECTIVE ACTION/COMMENTS
1. Faulty coaxial connection between DHU
and the interface device.
2. Faulty coaxial connection between interface
device and the BTS or donor antenna.
3. Faulty interface equipment.
4. Faulty DHU
5. Fault with cellular network or equipment.
1. Check forward path signals at the DHU. Check
reverse path signals at the interface device.
2. Check forward path signals at the interface
equipment. Check reverse path signals at the BTS or
antenna.
3. Adjust or replace interface equipment.
4. Replace DHU.
5. Contact cell service provider and verify that
cellular network and equipment is operational.
Alarm Type LED LED COLOR
None All Normal
Problem: Calls may be originated and terminated but service is noisy.
POSSIBLE CAUSE CORRECTIVE ACTION/COMMENTS
1. Some electrical device in the immediate
vicinity is creating interference.
1. Try turning off each device that may be causing
interference and see if problem corrects itself.
Alarm Type LED LED COLOR
None All Normal
Problem: Sudden high rate of blocked calls (delay dial tone).
POSSIBLE CAUSE CORRECTIVE ACTION/COMMENTS
1. Too many users for the number of channels
available.
2. Faulty DHU, DEU, or DRU.
1. Wait a few minutes and try dialing again. Upgrade
service if additional channels are required.
2. Replace defective unit.