Applies to: Full-fibre broadband, ONT equipment, UltraFast Fibre packages
Audience: Residential and small-business customers
Summary
A red LOS light on your ONT normally means the fibre signal is not being received correctly.
The ONT is the small device where the fibre connection enters your home or business. If the LOS light is red or flashing, your broadband service may be unavailable.
Important
Do not unplug or bend the fibre cable. Fibre cables are delicate and can be damaged if handled incorrectly.
Step 1: Check for local service issues
- Open the Nexora service-status page.
- Enter your postcode.
- Check for full-fibre faults or planned maintenance.
- If an outage is listed, follow the status update.
Step 2: Check the ONT power
Confirm that:
- The ONT power cable is connected.
- The wall socket is switched on.
- The power light is on.
- The ONT has not been accidentally switched off.
If the ONT has no power, try another socket if safe to do so.
Step 3: Check the fibre cable visually
Look for obvious signs of damage, such as:
- Cable sharply bent
- Cable pulled from the wall box
- Visible break
- Loose connector
- Recent building work near the cable route
Do not attempt to repair the fibre cable yourself.
Step 4: Check the SmartHub connection
The Ethernet cable should run from the ONT to the WAN port on the SmartHub or SmartHub Plus.
Make sure:
- The Ethernet cable is firmly connected at both ends.
- The cable is not damaged.
- The SmartHub is powered on.
- The SmartHub broadband light is not showing a separate router issue.
Step 5: Restart the equipment
- Turn off the SmartHub.
- Turn off the ONT, if it has a safe power switch.
- Wait 30 seconds.
- Turn the ONT back on first.
- Wait for the ONT lights to settle.
- Turn the SmartHub back on.
If the LOS light remains red, further investigation is likely needed.
When to create a support ticket
Create a ticket if:
- The LOS light stays red for more than 15 minutes.
- The fibre cable appears damaged.
- The ONT has power but no optical signal.
- There is no local outage listed.
- Service has not worked since installation.
- The issue affects a business service or priority customer.
