ALM-3598 Phase-Lock Loop alarm

Description

A DRU carries five phase-lock loops (PLLs): two sets of transmitting PLLs and receiving PLLs and one test PLL. This alarm is triggered when a receiving or transmitting RF phase-lock loop is out of lock, or the IOMU clock module fails.

Attribute

Alarm ID	Alarm Severity	Alarm Type
3598	Warning	Fault

Parameters

ID	Name	Meaning
1	Site No.	Number of the site where the faulty board or module is located Value range: 0-2047
2	Board Type	Number of the type which the faulty board belongs to. 135:DRU
3	Board No.	Number of the fault board 0:DRU0 1:DRU1
4	PassNo	Number of the passage where the faulty board is located.
5	SubLink No.	Alarm sub-category number 255:None
6	Cell Index	Index of the cell where the board or module is located 0-2047: Cell index of the faulty cell in the data configuration 65535: None
7	Site Type	Type of the site where the faulty board or module is located 9: BTS3002C
8	RackNo	Number of the rack where the faulty board is located.
9	BoxNo	Number of the subrack where the faulty board is located.
10	SlotNo	Number of the slot where the faulty board is located.
11	Site Name	Site Name
12	Alarm Attribute	Alarm Character 0:Normal 1:Transient Count

Impact on the System

When this alarm occurs, the DRU stops to output power.

System Actions

None.

Possible Causes

The MCU clock (13M clock) module becomes invalid.
The clock data line between the MCU and the DRU is disconnected.
The frequency configuration is incorrect (for example, the GSM900M BTS is configured with a frequency of DCS1800M).
The transmitting/receiving phase-lock loop is out of lock.
The DRU hardware is faulty.
The MCU hardware is faulty.

Procedure

Check whether there are any correlated alarms
Check whether the 3692 IOMU Clock Alarm or the 3654 DRU Clock Critical Alarm is reported on LMT.

Y=>Handle the 3692 IOMU Clock Alarm or the 3654 DRU Clock Critical Alarm according to the corresponding handling suggestions. Check whether the alarm is cleared .The alarm is cleared, Alarm handling is completed. The alarm is not cleared, Go to Step 2.

N=> Go to Step 2.
Check the BSC data configuration
Check whether the BSC data configuration is correct, especially the consistency between the ARFCN and DRU Type.
1. Check the "Assigned TRX" .
2. Check the configuration of the hopping frequency .
3. Check the property of the faulty DRU .
  Y=> The data configuration is correct. Go to Step 3.
  
  N=> The data configuration is incorrect. Modify the data configuration. Go to Step 3.
Reset the BTS
Perform fourth-level reset on the BTS3002C or reset it by power-down (recommended) through the LMT or local maintenance system. Check whether the alarm is cleared.

Y=> The alarm handling ends.

N=> Go to Step 4.
Remove and reinsert the MCU and DRU
Power down the BTS3002C. Remove and reinsert the modules on the backplane to ensure they are in well connection. Power up the BTS3002C and check whether the alarm is cleared.

Y=> The alarm handling ends.

N=> Go to Step 5.
Replace the MCU and DRU and see if the alarm is cleared
Y=>The alarm is cleared. Alarm handling is completed.

N=>The alarm is not cleared. Please contact Huawei Customer Service Center.