Step 2
Check for the possible causes on the ODN and troubleshoot the faults accordingly. If the ONU
still fails to be auto discovered by the OLT after that, proceed to
Possible Cause
Judgment Criterion
Troubleshooting Method
The optical fiber
connector is not clean.
NOTE
An unclean optical fiber
connector will cause
excessive attenuation and
abnormal reflection.
1. Test the backbone fiber and
branch fiber by using the
OTDR. It is found that the
reflection and return loss
are abnormal.
2. Check the optical fiber
connector on site by using
the optical fiber endface
detector. It is found that the
optical fiber connector is
not clean.
Clean the optical fiber
connector. For details about
how to clean the connector, see
2.2 Cleaning the Connector of
the Optical Fiber
.
The optical fiber is bent
excessively.
NOTE
Optical signals attenuate
seriously on an optical
fiber with an excessively
small bending radius.
1. Test the backbone fiber and
branch fiber by using the
OTDR. It is found that
abnormal return loss points
exist on the optical fiber.
2. Check the optical fiber on
site. It is found that the
optical fiber is bent
excessively.
Route and bundle the optical
fiber in a proper manner.
The optical fiber is not
firmly connected or
different types of optical
fiber connectors are
interconnected.
NOTE
If the optical fiber is not
firmly connected or
different types of optical
fiber connectors are
interconnected, the
attenuation and reflection
will be excessively large.
1. Test the backbone fiber and
branch fiber by using the
OTDR. It is found that
abnormal return loss points
exist on the optical fiber.
2. Check the optical fiber
connectors on site. It is
found that the optical fiber
is not firmly connected or
PC connector (blue) and
APC connector (green) are
interconnected.
l
If the optical fiber is not
firmly connected, reconnect
the optical fiber firmly.
l
If different types of optical
fiber connectors are
interconnected, replace the
incompatible connector
with a compatible one or
replace relevant devices,
such as the optical splitter.
NOTE
In the scenario of the CATV
service, it is recommended that
you use APC connectors (green)
only.
SmartAX MA5612 Multi-service Access Module
Maintenance Guide
6 System Fault Handling
Issue 01 (2012-07-25)
Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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