topic Re: Full Fibre overall est fix lead time for a LOS fault? in Full Fibre

Full Fibre overall est fix lead time for a LOS fault?

tarquel — Tue, 19 May 2026 20:30:00 GMT

Hi all.

Not sure how to term this but was wondering if there is a Full Fibre estimated lead time for fixes, when you have a LOS fault?

Naturally I'm expecting it varies dependant on the problem but I dont know if it is generally considered longer compared to copper based issues or not.

My situ is that last Wednesday, I started work (work from home) and things were being a bit ropey so I naturally assumed it was just my router / wifi mesh needing a poke that periodically sometimes happens and no big deal.

Managed to then join the meeting (that i was late for :D) but then within minutes, things seemed to crumble again, so this time I went to look at the ONT and saw that the LOS led was red and thought oh, maybe just needs a power cycle on the ONT as it wasnt clearing after sitting there watching it for a few mins...

Sadly after power cycling it, noticed the LOS and PON led's were lighting up in a intermittent ping ponging fashion (wasnt seemingly in any real order to it).

Don't remember exactly what happened after that - possibly I left it for a while doing that and it settled to just being LOS being red again or maybe I left it for a few mins and then tried another power cycle, not quite sure. Either way, it ended being just LOS red and staying that way. I didnt fiddle with any cables or the fibre itself and thought it best to use the report a fault SMS service (hadnt used it before).

The automated system ran a test and sure enough came back with a fault on the line and was able to book open reach engineer for the next available slot - which was on the Friday (just under two working days later, which was quite good).

The engineers visit was the lad was a nice chap, had a fiddle with the ONT initially, stuck a "laser" on the fibre and went off to try and trace it... came back an hour or two later and replaced it with a "stronger laser". At some point here I pointed out where the fibre ran (just in case) and he didnt seem realise that was the route so he went off to check that out.

Reappeared but next door, as the first pole the fibre went to was next door (of a sort) and I pointed him to the right way to get a response from the neighbour but he managed to find him and have a look at the pole there.

Eventually he came back and said that unfortunately there appeared to be something wrong with the fibre (i kinda gathered that :D). He did go off into a bit of detail but I didnt sadly catch all of it to remember everything. He said the the type of fibre was "blown" (and for some reason, the thought of a glass-blower came to mind :D) and that he doesnt do that and that would be a diff team that would need to reblow it or something, but then he also said that there maybe another way - something to do with another fibre on the panel (?) and that he might be able to come back on the saturday as he was working but would need another engineer with him and also would have to have the ok from his manager. He said they may not need to visit for that potential option really, but if we didn't hear from him, then it would likely need the other team to do the doo.

Saturday then rolled by and never heard anything.

I didnt have any sort of notifications after the initial SMS back and forth on the Wed - wasnt getting any emails oddly too - but its been a few years so wasnt sure what I was expecting there

Managed last night to find the Ticket that was generated and I notice from a message on it today that they mention regarding the fault, that a task "has been raised for an N11 (high skilled) engineer to attend site to complete a further investigation into the network issue", but I'm not sure if that is generic speak as didnt the first chap find what the problem was after all then?

Alas because I work from home, don't use satellite/antennas so generally stream media, and have smart homed a lot of the house (guess I should have looked at Home Assistant after all), it's quite disruptive (health issues in the mix for me too) so I'm unsure whether I should look to alternative connectivity methods for the time being (I can dual WAN with a USB 4G/5G dongle or smartphone apparently, although my data allowance is almost blown away in 4ish days already so...) or whether I'm jumping the gun a bit here and I just need to wait just another day or two longer (data sim has been ordered - just in case i need to activate it, assuming i can find a spare device to use :D) for more info on the situ.

Thanks for reading (if you've made it through all this :D) and any suggestions are welcomed.

Re: Full Fibre overall est fix lead time for a LOS fault?

markhawkin — Wed, 20 May 2026 10:27:17 GMT

I can possibly shine a little light.

"Blown fibre" is the old way that Openreach installed fibre. It is what it sounds like. A fibre is propelled by high pressure air down a tube to the far end.

My guess is that the first engineer "red lighted" it (using a visible light laser pen) to a point in the network where the onward fibre is "blown" . At that point, as the engineer wasn't trained to work on blown fibre, they stopped. The N11 (more experienced) engineer will come with the tools to find the break (including probably an Optical Time Domain Reflectometer).

With a domestic fault there isn't a contractual "time to fix" as far as I know.

Personally I would get some more data (perhaps a cheap SIM from a supermarket - one which mentions lots of data!) as when I had a fibre break on a domestic service it was more than a week to fix.

Re: Full Fibre overall est fix lead time for a LOS fault?

Baldrick1 — Wed, 20 May 2026 15:10:28 GMT

@tarquel

You will be receiving £10.34 per day compensation, so that should pay for quite a lot of data. See: https://www.plus.net/help/legal/automatic-compensation/

Re: Full Fibre overall est fix lead time for a LOS fault?

tarquel — Wed, 20 May 2026 20:56:42 GMT

Thanks for the reply @markhawkin

All sounds on point to me I only have experience of fibre in cabs (in a internal networking sense) with work and not really so much of that these days (comms guy is just too good to require me to assist, so my knowledge is wonky to say the least lol). Closest thing to (physical) networking i've done recently is terminating a cat6 link from next to the ONT, to where I've moved my router that was there [Asus GT6] over to the other side of the room 😁 - just to tidy things up, since that first engineer came PORT1 on the ONT is looking happy at least on that front but i can easily just plug the router directly in when the time comes following the fix

Also, have had a update on the ticket early evening to say "I have reviewed this fault and Chief Engineers (CE) estimate xxxxxxxxx has been raised to replace cabling" so thankfully it does look like they have determined its a fibre cable break or similar somewhere externally from the sounds of it so does seem on point to the thinking/what the first engineer was saying.

Ordered last night a new (free) data sim from my phone provider, so as this is likely going to be a few weeks I suppose so now I'm aiming to get my home wifi mesh I have with the Asus GT6 router with Dual WAN (well, just the backup WAN option at the moment of course :D) using a 4G/5G USB dongle or phone with that data sim I've ordered.

So if i can get it to work (dont have anything new enough/still works - bar possibly my partners old phone that should still work for 4G - but either way, will try that out to see if I have something that I can use to do that, and if it does work, then will get something specific (or just use my phone for the purpose and get a new phone lol) . Only about £18 for unlimited data for a month so not a biggie really additional data plan wise, its more finding out what device will work is what I'm needing to do now then i think

Can then run the router using that sim for a month (or roll the plan to another month, if it goes that long) and also have all the smart devices working and I wont have to faff about with enabling hotspot on my phone etc

@Baldrick1 Thanks for this mention - hadnt realised that was in place so thats good to know. If I do end up using my old phone for the purpose and it goes the full distance, then at least that will be a new phone cost sorted ha

Thanks both

Re: Full Fibre overall est fix lead time for a LOS fault?

tarquel — Sun, 31 May 2026 15:33:57 GMT

Text today to say your fault is fixed... huzzah? well sadly no, the saga continues...

After fair amount of days waiting, had a update on the ticket to say engineer booked to come on the morning of 29th May. Turns up fine and came with what I assume is the OTDR device that @markhawkin mentioned in the thread. Commented whilst it ran that unlike copper, he had no idea how it manages to do it on fibre Anyhoo, it stated it was 90-something Meters away. I explained where i knew of the route the fibre took, and after sticking a laser on the end of the fibre, off he went to see. Also took the duff BBU with him as they were meant to be removing those when they came across them (faulty or not) apparently.

About 45mins later, he came back and said he's found where the pole is where he believes the issue to be - explained a bit but my head cant recall the deets fully. Something about a container where the go into and in the heat the top dries out which makes the top come off slightly and shifts the container down onto the fibres or something. He also seemed surprised it was taking so long for this fault to be fixed too lol He came in saying that he hadn't had a update / response from his manager as he wasn't authorised to climb the poles and they'd need a specific person out for that, but as he was explaining his suspicions, he had a ding on his phone and had got word that a "joist" engineer was on the way to the pole. Dont remember what he said about whether he'd be back or not but picked up his laser and connected fibre back up to the ONT and he checked and my mobile was on the job, and off he went.

I didnt hear a peep and didnt hear a knock at the door or anything since.

Wasnt at home on Sat for the afternoon/evening as had to visit a family member in hospital but nothing was different when I got back.

When I woke up, i saw I had a text this morning to say the fault has been fixed etc. Great.... Went to look at the ONT and.....

LOS Red light still showing.

Left it until this afternoon and then powered it off for a minute and then back on again.

LOS Red light.

The ticket has been resolved and have attached what it looks like [with a bit of redaction where needed].but the test speeds for a start look wrong for a full fibre 900 surely? robot 19 has been a bad boy i think

Going to reply to the text as it suggests with ADVISOR to see what happens but thought I'd update here.

Re: Full Fibre overall est fix lead time for a LOS fault?

jab1 — Sun, 31 May 2026 15:46:56 GMT

@tarquel someone (or something is having a haugh. As you say, those supposed speeds are ludicrous - for any FTTP connection.

Re: Full Fibre overall est fix lead time for a LOS fault?

tarquel — Sun, 31 May 2026 16:07:03 GMT

Brief update as advisor called back and I explained the situ (effectively what I put in my last post). He checked the Openreach logging side and said it was pretty much what I had told him. Said that they haven't been able to complete the work but with it being the weekend, updates aren't so forthcoming there, so reopened the Plusnet ticket and said it will likely be tomorrow for an update on the situ from OR. Didn't really explain why a bot chose to line test some other line and close it so i defer to my earlier suspicion of a naughty robot

@jab1 😂 musta decided to test a ASDL line instead or something

Cheers