ALM-4702 CAN BUS Communication Abnormal

Description

This alarm is reported when the CAN main control module finds that the communication between the CAN node and CAN sub-nodes is faulty.

Alarm ID	Alarm Severity	Alarm Type
4702	Major	Fault

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. 87:GTMU
3	Board No.	Number of the fault board 0:GTMU
4	PassNo	Number of the passage where the faulty board is located.
5	SubLink No.	Alarm sub-category number 0: CANBUS0 faulty； 1: CANBUS1 faulty； 2: CANBUS0 and CANBUS1 faulty
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 is located. 17:DBS3900 GSM; 18:BTS3900 GSM; 19:BTS3900A GSM;
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

When one bus is faulty, the system automatically switches to the backup bus.
When the two buses are both faulty, the communication with the external devices fails, and the baseboards cannot monitor the clock and power.

When one bus is faulty, the system automatically switches to the backup bus.

Get the slot number of the faulty board according to 'Location info'. Plug and unplug the board in the slot. Check whether the alarm is cleared.
Y => The alarm is cleared. No further action is required.

N => The alarm is not cleared. Go to step 2.
If the alarm is generated in only one slot, replace the board in the slot. Check whether the alarm is cleared:
Y => The alarm is cleared. No further action is required.

N => The alarm is not cleared. Go to step 3.
When the alarms are generated in all the slots of the GTMU\UPEU\UEIU\UBFA, if the site is of the GSM+UMTS co-cabinet type, reset the WMPT board or unplug and plug the WMPT board. If the site is of the GSM only type, reset the GTMU board or unplug and plug the GTMU board. Check whether the alarm is cleared:
Y => The alarm is cleared. No further action is required.

N => The alarm is not cleared. Go to step 4.
Replace BBU. Check whether the alarm is cleared:
Y => The alarm is cleared. No further action is required.

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