ONUs (Optical Network Units) provide the interface between the fiber optic network and the home user. But sometimes connection issues can occur, causing service disruptions. Here are tips for troubleshooting common ONU problems:
Check that the ONU power adapter or Ethernet cable from the power injector is plugged in firmly.
Verify the power outlet is working. Try an alternate outlet.
If using PoE, substitute the Ethernet cable to rule out a damaged cable.
If the power light is still off, the ONU may be faulty. Contact technical support.
Inspect the fiber optic cabling from the outside plant for damage. Fix any bends or crimps in the cable.
Clean the fiber connectors on the cabling and ONU using compressed air. Reconnect firmly.
Try swapping the fiber optic cables going into the ONU's SFP module to determine if the issue is on the network or ONU side.
If optical loss is high, the outside plant cabling, splices or ONU's optical port may need replacement.
Check that the WiFi router and cabling connecting to the ONU is working properly. Try different Ethernet cables and ports.
Log into the ONU GUI and confirm IP addressing, DHCP setup and VLAN tags are correct.
Reset the ONU to factory settings in case the configuration was altered. Reconfigure if needed.
Verify authentication and registration of the ONU's serial number and credentials with the provider’s OLT.
Test wired speeds by connecting a computer directly to the ONU via Ethernet. This verifies maximum throughput to the ONU.
Run speed tests and check if other home devices are consuming bandwidth. Prioritize traffic using Quality of Service settings.
Inspect coaxial cabling and RF splitters if video service is slow. Amplify or replace if degraded.
The provider may need to allocate more bandwidth profile to the ONU based on the subscription.
On older ONUs, authentication uses PPPoE. Verify the PPPoE credentials match what was provisioned. Update if needed.
Newer ONUs use DHCP Option 43 for authentication. Confirm Option 43 settings match the OLT’s assigned value.
Factory reset the ONU and reconfigure from scratch if authentication issues persist. Contact support if problems continue.
Proactively monitoring and troubleshooting ONUs ensures subscribers enjoy uninterrupted fiber connectivity. Quickly resolving issues improves customer satisfaction.