What to do if the fiber optic light on an epon router turns red
Inspect the PON cable for make sure that it is correctly connected to the router. However, when it blinks red or stays solid red, it signifies a Loss of Signal, a problem preventing your router from communicating. If you find that the Optical/Config/PON Light on your Fibre ONT (Optical Network Terminal) box is flashing, has gone off, or has gone red, this indicates there may be an issue with the fibre connection coming into your property. The following article will explain why the Internet is light red and what you need to do to fix it.
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