User Manual

ADCP-75-110 • Issue 2B • July 2001
Page 43
© 2001, ADC Telecommunications, Inc.
4.3 Correct Installation Problems
Use the procedures outlined in Table 10 to troubleshoot various installation problems.
Table 10. Troubleshooting Installation Problems
PROBLEM 1 All LED indicators on the DHU or DEU stay off when the ON/OFF switch is placed in the ON position.
DHU OR DEU
= RED
= OFF
= GREEN
16432-A
POSSIBLE CAUSE CORRECTIVE ACTION/COMMENTS
1. AC power source is turned off.
2. Faulty AC power cord.
3. Faulty DHU or DEU.
1. Verify that the AC circuit breaker is turned on or
that a functional fuse is installed.
2. Test AC power cord and repair/replace as required.
3. Replace faulty DHU or DEU
PROBLEM 2 The UNIT LED indicator on the DHU or DEU is RED.
DHU OR DEU
= RED
= OFF
= GREEN
16433-A
POSSIBLE CAUSE CORRECTIVE ACTION/COMMENTS
1. Faulty DHU or DEU. 1. Replace faulty DHU or DEU
PROBLEM 3 The OVERDRIVE LED indicator on the DHU is RED.
DHU
= RED
= GREEN
16434-A
POSSIBLE CAUSE CORRECTIVE ACTION/COMMENTS
1. Forward path RF input level at the DHU is
too high
1. Reduce forward path gain by inserting additional
attenuation in the forward path signal.
PROBLEM 4
The OK/NOK LED indicator on the DHU or DEU is steady RED or blinking RED and the STATUS
indicator on the corresponding DRU is GREEN.
DHU OR DEU
FORWARD PATH LINK
REVERSE PATH LINK
DRU 3
= RED
= GREEN
16435-A
POSSIBLE CAUSE CORRECTIVE ACTION/COMMENTS
1. Faulty reverse path optical link.
2. Faulty optical transmit port at DRU.
3. Faulty optical receive port at DHU or DEU.
1. Test optical link and repair or replace as required.
2. Test DRU with optical loopback. Replace if faulty.
3. Connect optical link to another optical port at
the DHU or DEU. If problem is corrected,
replace the DHU or DEU.
PROBLEM 5
The OK/NOK LED indicator on the DHU or DEU is GREEN and the STATUS indicator on the
corresponding DRU is RED.
DHU OR DEU
FORWARD PATH LINK
REVERSE PATH LINK
DRU 3
= RED
= GREEN
16436-A
POSSIBLE CAUSE CORRECTIVE ACTION/COMMENTS
1. Faulty forward path optical link. (Early
version of DHU only)
2. Faulty optical receive port at DRU.
3. Faulty optical transmit port at DHU or DEU.
1. Test optical link and repair or replace as required.
2. Replace DRU.
3. Connect optical link to another optical port at
the DHU or DEU. If problem is corrected,
replace the DHU or DEU.
(continued)