Modem light occasionally flashes red for no reason

adrianlondon

Occasionally, my modem will flash the red LED for a minute or two, for no discernable reason.

The internet is working fine, logging in to the modem shows everything working as expected, and the Network Log has no entries at all for that period. It seems the red LED just decides to come on for a minute for fun.

Is there any other trigger for the red light that isn’t documented? It’s causing absolutely no problems so I don’t need it fixed or the modem replacing, I just want to know if it means anything 😁

Daniele_Sunrise

adrianlondon I can’t see anything right now that explains why the red light is flashing. Could you please note down the time and date next time, so I can quickly get in touch with the modem team to see if they can spot anything?

Greetings
Daniele

adrianlondon

Hi Daniele,

Thanks - I’ll do that! It doesn’t seem to be anything serious.

adrianlondon

Hi Daniele,

I’ll mark your answer as the solution, as it’s not happened again hence there’s nothing more to report.

adrianlondon

Hi again Daniele,

Well, guess what, soon after I posted the above, the problem came back 🙂

At 10:18 this morning, my modem was flashing red. It might have been doing that since I turned it on at 9:55am, but I only noticed it at 10:18, and as soon as I was paying attention, the red flashing went away.

I’ve also got a return of the bad picture quality on live TV, so I suspect it’s a cabling issue somewhere leading into my flat .

I know that Sunrise is probably wanting to move people onto fibre, and my internet does appear to be working perfectly, so it’s not the most urgent thing.

Daniele_Sunrise

adrianlondon Since your modem isn’t online, I’m afraid I can’t run a signal test. However, I can see a drop in the upstream signal between June 13 and June 14, which has happened repeatedly.

Greetings
Daniele

adrianlondon

Modem is full of these. Internet seems fine, though! It’s quite resilient 🙂

Xydocq

hello adrianlondon

Those messages indicate, that there’s something going on with the DOCSIS 3.1 channels. Downstream and Upstream channels seem to be affected.

Please check the values for Downstream and Upstream channels. This can be used as reference = https://linustechtips.com/topic/1597858-guide-to-cable-modem-signals/

adrianlondon

Thanks Xydocq. I assume my picture breakups on some live TV stations - mainly the BBC ones - is also related.

My figures for upstream/downstream look good. However, checking my network log, no errors/notifications have been written to it since 14:30.

I’ll check again next time I notice my logs full of those channel profile changes.

adrianlondon

oops! Sorry, I turned it off overnight. It’s back on now 🙂

What would cause those drops in the signal - cabling issues?

adrianlondon

Modem was flashing with a red light (while continuing to work perfectly!and nothing in the logs) just now.

11:19 CET

It’s gone back to it’s usual gentle white.

Daniele_Sunrise

adrianlondon As far as Signal is concerned, everything is fine. However, I have a suspicion as to what might be causing the issue. Could you please check if the LED light on the power supply is dimmer when the modem is lit up red? If so, I recommend calling 0800 707 707 to have the power supply replaced, as some defective power supplies are in circulation and do not provide enough power, which can lead to the issue you described.

Greetings
Daniele

adrianlondon

I’ll check next time it goes red. Thanks!