LOS light is red

Technical

1. A red LOS (Loss of Signal) light usually means the ONU is not receiving a stable optical signal.
2. Check that fiber connectors are seated and that the patch cable was not bent, pulled, or disconnected.
3. Avoid opening sealed optical ports yourself. If the LOS stays red after a restart, call support for a line check.
4. Share whether neighbors on the same building also lost service — that helps distinguish a single drop vs an area issue.

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