Specifications

75
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.