Failure Of An Ms To Search The Network; Table 11-3 Meanings Of The States Of The Liu Led (Uelp Not Used) - Huawei BTS3900 GSM Commissioning Manual

BTS3900 GSM
Commissioning Guide
After the physical loopback test is complete, you should restore the normal E1/T1 connection
at the DDF on the BTS side and ensure that the connection is proper.

11.3 Failure of an MS to Search the Network

This describes the fault symptom and analyzes the cause of the failure of an MS to search the
network.
Fault Symptom
An MS fails to find the network.
Cause Analysis
The possible causes are as follows:
l
l
l
Issue 03 (2008-07-15)

Table 11-3 Meanings of the states of the LIU LED (UELP not used)

If...
The LED is OFF,
The LED is ON or blinks at 4 Hz,
(5) Reconnect the E1/T1 cable to the OUTSIDE port on the UELP and ensure that the
connection is proper.
(6) Reconnect the INSIDE port on the UELP and the E1/T1 port on the GTMU with the
E1 transfer cable and ensure that the connection is proper.
CAUTION
The downlink signals are weak. Therefore, the MS is unable to locate the cell.
The downlink interference is strong. The MS is unable to locate the cell or receive the
correct downlink system information.
The cell radius is small.
NOTE
When the MS fails to find the network, pay attention to the output power of the local cell and the radio
network coverage.
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11 FAQs for BTS Commissioning
Then...
The UELP is faulty.
a. Check whether the connection
between the UELP and the backplane
of the BBU is reliable.
b. Replace the UELP with a new UELP.
The E1 link on the BTS side is not
normal, but the UELP is functional.
11-5