#1 What the ONT is — and why it is not the router
Every Fios home has an Optical Network Terminal: the box where Verizon’s fiber converts to the wiring your router uses. In most homes it sits apart from the router — in a basement, garage, closet or on an outside wall — and it is easy to mistake for “the router’s power brick” or a mystery box. Two facts frame every support decision on this page (S27):
- The ONT is the front door for all Fios services. Verizon states plainly that the ONT “requires electricity to operate all Verizon Fios services” — internet, TV and phone.
- It is Verizon equipment. The ONT page documents no user-reset, no model-specific instructions, and no serviceable parts. Support flows through Verizon, not through a button.
If your internet is down but the Wi-Fi lights on your router look normal, the ONT is exactly the device to check first — and the router guides (CR1000A, G3100) are where the Wi-Fi half lives.
#2 The one indicator Verizon documents
Verizon’s ONT page documents a single light (S27):
- On — electrical power is present. “During normal operation, the light should be on.”
- Off — “electricity is not flowing from the outlet.”
That is the complete official light documentation for the ONT. No blink states, no color table, no model-specific legends — and this site deliberately does not invent any. If your ONT’s light is blinking, the honest reading is “not documented”: check power first, then service, then contact Verizon. The ONT blinking guide applies the same discipline to the specific blinking question.
#3 The power rule — and the battery
Verizon’s instruction is absolute (S27): “Ensure connectivity to the Verizon Fios Network by making sure your ONT power supply unit stays plugged in at all times.” Practical consequences:
- Do not unplug the ONT as a troubleshooting step. Unlike a router, there is no documented unplug-and-wait procedure — unplugging drops internet, TV and phone together, and there is no documented benefit.
- The outlet matters as much as the device. If the indicator light is off, Verizon’s page points at the electricity, not the terminal: check that the outlet works before assuming the ONT has failed.
- Voice customers have a battery — Verizon links to Battery Backup Information as the dedicated support route for the ONT’s battery (S27). The battery keeps phone service alive during power outages; its care and replacement are documented there, not improvised.
#4 When the light is on but service is wrong
The ONT page defines the escalation path precisely (S27): if the indicator light is on and you are experiencing service issues, use the Guided Solutions Tool “to see if there are issues occurring with your equipment or service line.” That tool is also Verizon’s named outage-checking route (per the outage guide) — so one flow covers both questions: is it my equipment, my line, or an outage?
The sequence for a dead or degraded Fios connection:
- ONT power light: on → power is present; off → fix the outlet/power path first (S27).
- Guided Solutions Tool — equipment or service-line diagnosis, outage information included (S27).
- Router checks — if the ONT is powered and the tool finds no line issue, the fault is likely in the router half: the CR1000A and G3100 support pages carry their documented restarts and light tables.
- Contact Verizon with the outcome of steps 1–3 — the tool’s result plus the ONT light state is the evidence support acts on.
#5 What this page deliberately does not cover
Three boundaries, each for a documented reason:
- No reset procedure. Verizon documents none for the ONT (S27), and the equipment is Verizon’s. Any “hold the reset” advice you find elsewhere for an ONT is not from Verizon.
- No blink-code table. The source describes a power indicator only (S27). Blinking is undocumented — the blinking guide explains what to do instead of guessing.
- No model-specific instructions. The page names no ONT model; the Alcatel-Lucent, Nokia and Motorola units in Verizon homes are not described individually (S27).
#6 Common ONT questions
Q: The ONT light is off but the router works. How? If the router has power and a connection, the ONT’s light being off is odd — check the outlet and the power supply seating first (S27: light off means electricity is not flowing from the outlet). If the outlet is live and the light stays off, that is a Guided Solutions Tool / Verizon support case.
Q: Can I move the ONT or hide it in a cabinet? It is Verizon’s equipment, and its power supply “stays plugged in at all times” (S27). Relocation is a Verizon technician’s job — a self-install move risks the fiber connection and the phone battery, and is not documented for self-service.
Q: My phone works but the internet is down (or the reverse). All Fios services ride the ONT (S27), so a partial failure points past it: run the Guided Solutions Tool, and check the router half via the CR1000A or G3100 support pages. The ONT’s own documented state is just the power light — it cannot tell you which service failed.
Q: Power is out in my neighborhood — will Fios phone still work? Voice customers have battery backup for exactly this case (S27, per the Battery Backup Information route). Internet and TV stop with wall power unless you have separate backup; the battery’s job is the phone line.
#7 Related pages
- Fios ONT blinking — why blinking is undocumented and what to check instead.
- CR1000A support — the router’s documented restarts and light table.
- G3100 support — the Fios Router’s own manual, holds and LED states.
- Check for an ISP outage — the Guided Solutions Tool in context.