01/01/01 08:15 Status Indications and Alarms 5-1
Chapter 5Troubleshooting andDiagnostics

5.1 General

This chapter describes the HCD-E1 diagnostics functions, which include:
• Status indications and alarms - Section 5.2
• Performance diagnostics - Section 5.3
•
Diagnostic loopbacks - Section 5.4
• Configuration error messages - Section 5.5
•
Power-up self-test - Section 5.6
•
Troubleshooting instructions - Section 5.7.

5.2 Status Indications and Alarms

Front-Panel LEDs The status of HCD-E1 is indicated by the ALM, TST, E1 LOS and HDSL LOS
LED indicators located on the front panel. For description of LED indicators
and their functions, refer to Table 3-1 and Section 3.5, Operating
Instructions, in Chapter 3.
Alarms HCD-E1 maintains an alarm buffer, which can store a maximum of
100 alarms. Alarms can be of two types, designated as ON/OFF and ON:
• A message indicating an ON/OFF-type alarm is displayed on the LCD
only when the alarm condition is present, and is automatically stopped
from being displayed when the alarm condition is cleared (if the alarm is
being displayed, it will disappear only when the display is refreshed by
scrolling).
• A message indicating an ON-type alarm still can be displayed on the LCD
even after the event that caused the alarm condition is cleared.
In this manual, we often use the term ON-state alarm. An ON-state alarm is
either an ON-type alarm or an ON/OFF-type alarm when its alarm condition
is still present.