ONU Fault

Procedure

Check for the possible causes on the ONU and troubleshoot the faults accordingly.

Possible Cause

Judgment Criterion

Troubleshooting Method

The ONU is not powered on.

Check the power supply of the ONU. It is found that the power supply of the ONU fails or is turned off.

Restore the power supply of the ONU.

A rogue ONU exists on the network and affects other ONUs.

NOTE:

If a rogue ONU exists, the ONU that fails to go online may be a normal one and the ONU that can go online may be a rogue one.

If either of the following two situations occurs, a rogue ONU exists.

  • The 0x2e314021 There are illegal incursionary rogue ONTs under the port alarm is generated on the OLT.
  • The 0x2e314022 The ONT is rogue ONT alarm is generated on the OLT.
  • Remove the optical fiber from the OLT port and connect the optical fiber to the optical power meter for measurement. If a value can be read from the optical power meter, a continuous-mode ONU or irregular-mode ONU exists.
NOTICE:

Measuring the optical power interrupt services, Therefore, it is recommended that you measure the optical power when a PON port does not run any services, such as deployment.

Replace the rogue ONU with a normal one.

The ONU hardware is faulty.
If either of the following two situations occurs, the ONU hardware is faulty.
  • The LEDs of the ONU are off when the ONU is powered on.
  • After the ONU is replaced with another ONU, the new ONU is auto discovered by the OLT.

Replace the faulty ONU or the optical module of the ONU.

The optical module of the ONU is abnormal. For example, the transmit optical power of the optical module is excessively small or its receiver sensitivity is low.

Replace the faulty ONU with a normal one. It is found that the new ONU is auto discovered by the OLT.

An alternative is to locate the fault as follows:
  • Set the optical module of the ONU to the continuous mode, and measure the transmit optical power by using the optical power meter. It is found that the actual transmit optical power is beyond the normal range (0.5 dBm to +5 dBm).
  • Measure the receive optical power of the ONU by using the optical power meter. It is found that the actual receive optical power is within the normal range (-27 dBm to -8 dBm).
NOTE:
The transmit optical power of a 10G GPON optical module ranges from 2 dBm to 7 dBm, and the receive optical power ranges from -29.5 dBm to -9 dBm.

Replace the faulty ONU or the optical module of the ONU.

The Patch cord of the ONU is broken or bent excessively.

Check the Patch cord of the ONU. It is found that the Patch cord is broken or bent excessively.

Replace the Patch cord of the ONU.

Next:Collecting Information and Seeking Technical Support

Previous:ODN Fault

Back

Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.