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FTTP Modem Lights Explained
Last Updated: Sunday 14 Sept 2025
There are 3 versions of the Fibre to the Premises (FTTP) modem, also called an Network Termination Device (NTD).
Check the images below for the version that looks like yours.
| Indicator | Status | Description | Action |
|---|---|---|---|
| Power | Off | No power | If an extension cord, power board or AC UPS is used with the NTD, disconnect these devices, plug the NBNCo Power Supply directly into the AC outlet and make sure that the AC supply is turned on |
| Power | Solid red | Operating from battery - if main power is off | None |
| Power | Solid green | Operating on AC power | None |
| Power | Flashing green | NTD is starting up | None |
| Optical | Off | NTD is disabled | None |
| Optical | Solid red | Optical link is disconnected | Check optical patch lead is seated fully in Optical Port and not excessively kinked |
| Optical | Solid green | Optical link is connected | None |
| Optical | Flashing green | Activity | None |
| Alarm | Off | NTD is operating without failure | None |
| Alarm | Solid red | NTD hardware failure | Contact our support team on 1300 880 905 |
| Alarm | Solid green | No alarm, with local Ethernet access enabled | None |
| UNI D1 to D4 | Off | No service provisioned or no link detected | None |
| UNI D1 to D4 | Solid yellow | 1G link detected | None |
| UNI D1 to D4 | Flashing yellow | 1G data activity | None |
| UNI D1 to D4 | Solid green | 10/100 link detected | None |
| UNI D1 to D4 | Flashing green | 10/100 data activity | None |
Power
Indicator | Meaning | Action |
Off | There is no power to your NBN connection box. | Check the power supply is plugged in and switched on and is connected to your NBN connection box. If there is still no power light, contact your provider. |
Green – slow flashing | Your NBN connection box is starting up. | No action is required. The flashing light should turn into a green solid light shortly. |
Green – fast flashing | Your NBN connection box is getting a firmware update. | No action required. |
Green - solid | Your power supply is working normally. | No action required. |
Optical
Indicator | Meaning | Action |
Off | Your NBN connection box is not connected to the NBN network. | Raise a fault through MyAussie, or get in touch with our team via LiveChat, or giving us a call. |
Green – steady light | The NBN connection box is connected to the NBN network and can receive data. | No action required. |
Green – slow flashing | Your NBN connection box is connected and receiving data. | No action required. |
Red | Your NBN connection box has lost connection. | Raise a fault through MyAussie, or get in touch with our team via LiveChat, or giving us a call. |
Alarm
Indicator | Meaning | Action |
Red | Your NBN connection box has a fault and is not working normally. | Raise a fault through MyAussie, or get in touch with our team via LiveChat, or giving us a call. |
Off | Your NBN connection box is operating normally. | No action required. |
Port 1
Indicator | Meaning | Action |
Off | The Wi-Fi router is not connected to the NBN connection box. | Check your Wi-Fi router is correctly plugged in to the NBN connection box. |
Green – fast flashing | There is an active service and data is being transferred through the port. | No action is required. |
Green | There is an active service but data isn't being transferred through the port at the moment. | No action is required. |
Power
Indicator | Meaning | Action |
Off | There is no power to your NBN connection box. | Check the power supply is plugged in and switched on and is connected to your NBN connection box. If there is still no power light, contact your provider. |
Green – slow flashing | Your NBN connection box is starting up. | No action is required. The flashing light should turn into a green solid light shortly. |
Green – fast flashing | Your NBN connection box is getting a firmware update. | No action required. |
Green - solid | Your power supply is working normally. | No action required. |
Optical
Indicator | Meaning | Action |
Off | Your NBN connection box is not connected to the NBN network. | Raise a fault through MyAussie, or get in touch with our team via LiveChat, or giving us a call. |
Green – steady light | The NBN connection box is connected to the NBN network and can receive data. | No action required. |
Green – slow flashing | Your NBN connection box is connected and receiving data. | No action required. |
Red | Your NBN connection box has lost connection. | Raise a fault through MyAussie, or get in touch with our team via LiveChat, or giving us a call. |
Alarm
Indicator | Meaning | Action |
Red | Your NBN connection box has a fault and is not working normally. | Raise a fault through MyAussie, or get in touch with our team via LiveChat, or giving us a call. |
Off | Your NBN connection box is operating normally. | No action required. |
Port 1, Port 2, Port 3 or, Port 4
Indicator | Meaning | Action |
Off | The Wi-Fi router is not connected to the NBN connection box. | Check your Wi-Fi router is correctly plugged in to the NBN connection box. |
Green – fast flashing | There is an active service and data is being transferred through the port. | No action is required. |
Green | There is an active service but data isn't being transferred through the port at the moment. | No action is required. |
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