If you have Verizon FiOS internet and notice the red “Fail” light illuminated on your optical network terminal (ONT), it indicates there is a problem that needs to be addressed. The fail light signals an issue preventing the ONT from operating normally and delivering your FiOS services.
What Causes the ONT Fail Light?
There are several potential causes for the Verizon ONT fail light to activate:
1. Power Issues
The fail light will turn on if the ONT is not receiving sufficient power from its supplied power adapter. Ensure the unit is plugged directly into a wall outlet and not a power strip or surge protector.
2. Fiber Optical Cable Problems
Since the ONT connects to Verizon’s fiber network, any damage to the incoming fiber optic cable itself can trigger the fail condition. Crimped, cut or loose fiber cables need repair.
3. Failed Component
It’s possible for internal hardware components within the ONT to simply fail, especially in older ONT models that have been in service for years.
4. ONT Overheating
The ONT fail light may also activate if the device is overheating due to poor ventilation or environmental conditions where it’s installed.
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Troubleshooting Steps To Fix Verizon Ont Fail Light
If your Verizon ONT has the red fail light on, start basic troubleshooting:
- Reboot the ONT by unplugging it, waiting 15 seconds, and then reconnecting the power.
- Check all cable connections to the ONT are secure with no damage.
- Ensure no cords are crimped and the fiber optic cables are not bent at extreme angles.
- Relocate the ONT if its current location is poorly ventilated or gets too hot/cold.
- If accessible, try replacing the existing fiber optic cables with new ones.
- Replace the ONT power adapter with a new one if available.
If the fail light persists after exhausting self-troubleshooting steps, the next course of action is to contact Verizon technical support. They can further remotely diagnose the ONT status.
In some cases, a technician may need to come on-site to inspect the ONT and fiber optic lines directly. The fail light indicates an issue requiring repair to restore full FiOS services through the optical network terminal.