FTTP connection box lights and checks
With Fibre to the Premises (FTTP), fibre runs all the way into your building and ends at an nbn connection box mounted on an inside wall. Your router plugs into that box with an Ethernet cable. Not sure FTTP is what you have? See which nbn connection do I have.
Don’t touch the fibre cable. Don’t unplug, bend or unloop the thin fibre cable going into the box. Even unplugging it can damage the connection, and fixing that needs a technician. Never look into the end of a fibre cable.
Which box do you have?
There are three kinds of FTTP box:
- New one-port box (installed from September 2025): a small square white box with four lights (Power, Optical, Alarm, Port) and one orange Ethernet port.
- New four-port box: the same style with seven lights (Power, Optical, Alarm, Port 1 to Port 4). Port 1 is grey and Ports 2 to 4 are orange. Each port carries a separate service, so businesses with more than one nbn service usually have this one.
- Previous box (most boxes installed before September 2025): a larger box with lights for Power, Optical and Alarm, four data ports labelled UNI-D 1 to 4 and two phone ports labelled UNI-V. Some have a separate power supply with a battery back-up.
The ports are on the underside of the box, behind the wall-mount cover. On the new boxes, press in the sides of the cover and slide it down.
Check your router is in the right port
On a new one-port box, the router goes in the orange port labelled Port. On a four-port box or a previous box, your service is assigned to one particular port. Plugging into a different port won’t work. If you don’t know which port is yours, ask us and we’ll check.
What the lights mean: new one-port and four-port boxes
| Light | What you see | What it means | What to do |
|---|---|---|---|
| Power | Solid green | Power is fine and the box is ready | Nothing |
| Power | Slow green flash | The box is starting up | Wait. It goes solid shortly |
| Power | Fast green flash | The box is installing an update | Wait. It goes solid shortly |
| Power | Off | No power reaching the box | Check the power supply is plugged in, switched on at the wall and connected to the box. Still off? Contact us |
| Optical | Solid green | Connected to the nbn network | Nothing |
| Optical | Slow green flash | Data is moving on the nbn connection | Nothing. It goes solid shortly |
| Optical | Off | Not connected to the nbn network | Contact us |
| Optical | Red | The connection to the nbn network has been lost | Contact us |
| Alarm | Off | Working normally | Nothing |
| Alarm | Red | The box has a fault | Contact us |
| Port (or Port 1–4) | Solid green | Connected, but no traffic at this moment | Nothing |
| Port (or Port 1–4) | Fast green flash | Connected and traffic is passing | Nothing |
| Port (or Port 1–4) | Off | Your router isn’t connected to this port, or no service is active on it | Check the router’s cable is firmly in the right port. Still off? Contact us |
All the lights dark? The box has a LIGHTS ON/OFF button that turns the lights off without affecting the connection. The lights won’t come back on by themselves, so press it before deciding the box has no power.
What the lights mean: previous box
| Light | What you see | What it means | What to do |
|---|---|---|---|
| Power | Green | Power is fine | Nothing |
| Power | Green flashing | The box is starting up | Wait. It goes solid shortly |
| Power | Red | Mains power is off and the box is running on its back-up battery | Services keep working for up to about five hours. See the battery section below |
| Power | Off | No power reaching the box | Check the power supply is plugged in, switched on and connected. Still off? Contact us |
| Optical | Green or green flashing | Connected and working | Nothing |
| Optical | Red | The connection to the fibre network has been lost | Contact us |
| Optical | Off | The box has been disabled from the network side | Contact us |
| Alarm | Green | Working normally | Nothing |
| Alarm | Off | Working, but nothing is connected to it | Nothing, unless your router should be connected |
| Alarm | Red | The box has a fault | Contact us |
| UNI-D (data ports) | Orange or green, steady or flashing | A device is connected. Orange means a 1 Gbps link, green means 10 or 100 Mbps | Nothing |
| UNI-D (data ports) | Off | No active device on this port right now | Check the router is connected to your assigned port |
If the UNI-D light for your router’s port is green rather than orange, the link to your router is running at 100 Mbps or slower. Mention that when you contact us if your speeds are low.
If the internet isn’t working
- Check the Power light is on. Check the power point is switched on and every cable is pushed in firmly.
- Check the Optical light. If it’s red or off, the problem is on the nbn side. Skip to step 6 and contact us.
- Make sure the router’s cable is in the port assigned to your service.
- Turn the router off and on again.
- Try a different Ethernet cable between the box and the router.
- Still not working? Unplug the router’s cable from the box and plug a laptop straight into that port instead. If the laptop gets online, the problem is the router. If it doesn’t, the problem is the connection. Either way, log a fault or call 1300 049 749 and tell us what you found.
The box has a small Reset button that needs a paperclip. Only use it if we ask you to: a short press restarts the box, but holding it longer than 5 seconds wipes it back to factory settings.
If a fallen branch or building work has damaged the fibre cable outside, don’t try to move or fix it. Contact us straight away.
For general checks that apply to every connection type, see internet down: first checks. For slow speeds, see slow or dropping out.
Battery back-up alarms
Some older FTTP installations (before June 2024) have a separate power supply unit with a back-up battery. nbn no longer installs these. If you have one:
- During a power cut, the battery keeps the nbn box running for up to about five hours. It powers only the nbn box. Your router, phones and alarms need their own back-up power.
- A red light beside Replace Battery plus a beep every 15 minutes means the battery needs replacing.
- Four beeps a minute means less than half the battery charge is left.
- Keep the power supply plugged in and switched on. Switching it off and on often shortens the battery’s life.
- The replacement is a standard 12 V 7.0–7.2 Ah sealed lead-acid battery (F2 terminals), sold by battery retailers. Take the old one to a battery recycler, not the bin.
- Don’t open the power supply except to change the battery. Some parts stay live even when it’s unplugged.
- If you don’t need battery back-up any more, tell us and we can stop the reminders.
Moving?
Leave the nbn box behind. It’s set up for that address and won’t work anywhere else.
Before you call us
Have this ready so we can lodge the fault with nbn quickly:
- Which lights are on and their colours, after watching the box for about a minute
- Which kind of box you have (one-port, four-port or previous), and which port your router is in
- What you’ve tried, including whether a laptop plugged straight into the box worked
- Whether the whole office is down. If it is, we treat it as urgent.
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