Trying to fix an ethernet connection (RJ45 cable into a wall socket) - Page 1
Forum section: electronics / beginners

author: st1led
author_rank: Contributor
timestamp: November 01, 2020, 08:15:53 pm
content: Hello everyone!I just got into a new house where I have an Ethernet wall socket which ends with an Ethernet cable to my router. This wall socket wouldn't work 99% of the time, as no connection is detected when plugging the cable in my laptop. After hours of plug on/off, I seldomly manage to get that working for some time, albeit being significantly slower than my connection when connecting directly to the router via Ethernet (90/90 while it should be 750/750).This makes me think there might be a poor contact rather than a straight terminated wire -- else I wouldn't be able to seldomly connect. This might also explain the relatively slow speed whenever I manage to connect. I exclude it's a laptop/software/cable issue because I can connect just fine to other wall sockets with the same Ethernet cable and laptop.I took off the socket cover and started investigating a bit (I attach a couple of pictures). I managed to find the socket online, which is I think one of these two:https://proff.elko.no/modularuttak-kat-6-utp/plus-1xrj45-utp-kat-6-i-ph-article1931-903.htmlhttps://proff.elko.no/modularuttak-kat-6-utp/rs16-mod-i-1x8-kat-6-utp-ph-article1829-903.htmlNot sure which one exactly, but the cabling instructions seem identical. The wire pairs seem to be installed correctly (T568B): white5-blue4, white1-orange2, white3-green6, white7-brown8. The other end of the socket just looks like a regular Ethernet cable, and it goes into the router "clicking" just fine. I got a network tester and found out that wire #2 is not working: the light doesn't light up in the sequence, while all others do. That should be the orange wire.I tried to re-connect the orange cable to the circuit board on the wall socket with a punch-down tool. Still wire #2 not working. Also tried disconnecting and reconnecting another wire to get a feedback from the tester, the wire i disconnected didn't light up in the test and eventually did when I punched it down again.I tried to fix a new connection on the other end of the cable, cutting the cable and crimping a fresh new RJ45 connector. Probably not the cleanest job you've seen (more pics attached), yet the tester says all wires but #2 are working.Any ideas? Could it be an issue in the socket PCB? I think it's almost impossible that the orange wire is cut somewhere in the middle of the cable, but everything can happen I guess.

author: tooki
author_rank: Super Contributor
timestamp: November 01, 2020, 11:00:22 pm
content: Well it's certainly easy enough to test whether the orange wire itself has continuity.Note that the jack itself is poorly installed: the pairs need to maintain the twisting all the way up to the punchdown block, not be straightened out like here. If you look at the instructions for the jacks you linked to, they even say this explicitly and show how close the cable should be.

author: S. Petrukhin
author_rank: Super Contributor
timestamp: November 02, 2020, 04:47:44 am
content: This plug is bad.

author: S. Petrukhin
author_rank: Super Contributor
timestamp: November 02, 2020, 04:50:24 am
content: Quote from: tooki on November 01, 2020, 11:00:22 pmThe standard allows for 2cm unwinding of pairs on both sides. In real life, at 10/100Mbit and more.

author: tooki
author_rank: Super Contributor
timestamp: November 02, 2020, 07:04:06 am
content: Quote from: S. Petrukhin on November 02, 2020, 04:50:24 amBut that looks like more than 2cm, and the goal is gigabit, which is at the outer limits of what that Cat 5/5e cable can handle. Mind you, we know it wasn’t the source of the problem, which is the broken orange wire, I was just pointing out good practice.

author: st1led
author_rank: Contributor
timestamp: November 02, 2020, 08:07:38 am
content: Quote from: tooki on November 01, 2020, 11:00:22 pmYes, I noticed that there is too much untwisted wire until the punchdown block, but I don't think that's the source of the issue, is it?How would you test the orange wire? Cut the end with the RJ45, strip the orange wire, and then use a multimeter tester? The problem is that the ends are in different rooms, so I might need some special tool for that.

author: st1led
author_rank: Contributor
timestamp: November 02, 2020, 08:08:54 am
content: Quote from: S. Petrukhin on November 02, 2020, 04:47:44 amDo you mean the connector itself, or the connection? Yes, I think the wires should all be aligned, but I didn't really manage to. I'll give it another try, but still it seems to work for 7/8 of the wires...

author: Jwillis
author_rank: Super Contributor
timestamp: November 02, 2020, 08:10:57 am
content: That orange wire is the RX- is the receive data for 10Base-T and 100Base-T or Bidirectional data - for the 1000Base-T . In either case if disconnected you won't be able to receive Data..As Tooki mentioned it looks like a poor installation so check where the cable comes into the house. I had similar problems a few years ago because of poor installation. Turned out to be corroded wires.

author: st1led
author_rank: Contributor
timestamp: November 02, 2020, 09:09:28 am
content: Quote from: Jwillis on November 02, 2020, 08:10:57 amThe cable is inside the house and doesn't really come from outside. One end of it is the wall socket, the other is a RJ45 connector ending up in a closet in a different room. This connector is intended to be put into a router (connected via WAN through another cable coming from outside, which luckily is working).

author: Ranayna
author_rank: Super Contributor
timestamp: November 02, 2020, 10:58:33 am
content: Crimping a connector like that directly on solid core network cable will not be reliable. Better to use a plug on both ends. You can use something like this:https://www.amazon.de/DIGITUS-Professional-geschirmt-10GBase-T-werkzeugfreie/dp/B00609TMEU/ref=sr_1_3?__mk_de_DE=%C3%85M%C3%85%C5%BD%C3%95%C3%91&dchild=1&keywords=netzwerk+buchse&qid=1604314513&sr=8-3You don't even need special tools for these, just some pliers and a flush sidecutter.If you want it properly wall mounted, there are boxes available where that jack snaps in properly.I would recommend getting two and redoing both endsGet a cheap network tester that shows you if the pairs are actually all correct. I see a cheap one on Amazon for 7 Euro, that should be enough to point out any obvious issues.

author: S. Petrukhin
author_rank: Super Contributor
timestamp: November 02, 2020, 11:32:44 am
content: Quote from: st1led on November 02, 2020, 08:08:54 amI have not seen plugs that have wires at different levels arranged in turn. They should turn into a flat cable inside the plug.And if you want to get Gigabit, distance and dented cable may be the reason. Here it is true that the category 5e works at the limit of its capabilities. Try switching the link to 100Mbit - why do you need a Gigabit for the Internet?

author: Ian.M
author_rank: Super Contributor
timestamp: November 02, 2020, 11:42:32 am
content: That cable looks deeply suspicious.Ignoring the issue of Ethernet wire categories, there are two basic types of UTP Ethernet cable, solid core for infrastructure (fixed) wiring, and stranded for patch leads and other applications where the cable is likely to be subject to movement. The IDC connectors are *NOT* compatible, as one intended for solid wire wont form a reliable connection to stranded wire.The builder *should* have used Cat 5e or better infrastructure (solid core) copper wire, terminated on the punchdown block of a socket at both ends, so you can connect your device and router via patch leads. Instead *I* *think* they hacked the end off a long patch lead (you can tell if there's an overmoulded strain relief that the plug was factory fitted, so if so it must be a patch lead), and bodged it into the punchdown block of a socket, 'saving' the cost of terminating wiring properly at the router end.Hopefully the wire isn't CCA (copper clad aluminum), which I posted how to identify, or CCS (copper clad steel), which is readily identifiable with a small magnet. If its CCA or CCS, the best thing you can do is rip it out, using it to pull through real copper Cat 5e or better infrastructure cable, and terminate that properly with a new socket at each end.Assuming the wire is a real Cat 5e patchlead, the question then becomes how to salvage the link. IMHO the best option would be to terminate it with a RJ45 plug (and test it), and either plug it into a Cat 5e or better RJ45 F-F coupler (extender), which you'd have to bodge onto the faceplate to present as a fixed socket, or strip the small PCB carrying the socket and punchdown blocks from a modular RJ45 socket (or use the whole module if its small enough) and use it to connect to a short length of real copper solid core Cat 5e or better cable which will be compatible with the punchdown blocks on RJ45 sockets. If necessary add insulation so it cant short to the metal back box.N.B. you cant terminate wire to punchdown blocks reliably without a proper punchdown tool that pushes the wire down evenly without damaging the contact blades. The plastic disposable ones are pretty cheap and with care, are good for at least 50 connections, i.e. four fully wired RJ45 sockets. If you used a screwdriver or other non-standard tool to punch down the wire, odds are you've damaged the socket contacts, either bruising the sharp edge that's supposed to make a gas-tight contact to the wire, or spreading the forked contact, so you should replace the socket.N.B.2 10base-T and 100base-T ethernet only requires two pairs of wires, pins 1, 2, 3 & 6, which are normally the green and orange pairs, so if a wire is broken in an infrastructure cable and you absolutely cant replace the cable, you can swap pairs at both ends to connect those pins, leaving the other two pairs unconnected, and get a reliable lower speed link. You *MUST* *NOT* split pairs, i.e. 1 & 2 must use a single twisted pair, and 3 & 6 another. Also take care not to reverse a pair at one end!'Fixes' I would not recommend: Attempting to splice solid core UTP to stranded UTP - It can work at 10Mbps and even 100Mbps if you are careful not to disturb the twist of each pair and keep the splices really neat and short (under 1cm), but the chances of it working reliably for gigabit Ethernet are poor. Desoldering the punchdown block and soldering the stranded UTP wires direct to the socket PCB - again its likely to be problematic for gigabit Ethernet.Edit: Some comments below and close inspection of your plug photo are causing me to rethink it being stranded patchlead cable. If its solid wire, and not CCA or CCS, I'd recommend simply terminating it with a new socket at each end.

author: wraper
author_rank: Unknown
timestamp: November 02, 2020, 11:44:23 am
content: It's not about untwisted wire at the ends, ethernet is too robust to care about that. Also the vast majority of cable testers simply test connectivity, no high frequency signal. 100 mb ethernet uses only 2 twisted pairs. Gigabit ethernet uses all 4 twisted pairs. So if there is something wrong with twisted pairs it's likely that only 100 mb speed will work.

author: tooki
author_rank: Super Contributor
timestamp: November 02, 2020, 11:48:13 am
content: Quote from: Ranayna on November 02, 2020, 10:58:33 am1. You mean “socket”, not “plug”. (Socket = Buchse, Plug = Stecker)2. They make Ethernet plugs for solid wire.

author: Ian.M
author_rank: Super Contributor
timestamp: November 02, 2020, 11:59:42 am
content: They *do* make RJ45 plugs for solid wire (and its a major foulup to mix them up with your stock of plugs for stranded wire), but the O.P's photo shows an overmoulded strain relief on the router end of the cable, so odds are better than 99% he's actually got stranded patchlead in his wall! Therefore a solid core RJ45 plug wont help . . .

author: Ranayna
author_rank: Super Contributor
timestamp: November 02, 2020, 01:06:06 pm
content: You are of course right about that plug/socket issue. I always get that confused, sorry.And yes, i have overlooked that the cable with the plugis a different color. If that plug is really overmolded is not clear in the picture. I cant imagine that it is, it would be almost impossible to remove the cable from such a plug without damaging the plastics. Also that front on image looks like a not fully slipped in place cover. I have worked with similar plug ages ago.So, there is some interface somewhere between the gray cable coming out of that wall box and that cable with the plug. Another potential location for a fault. Hopefully there is not something like this somewhere in an attic:

author: mikerj
author_rank: Super Contributor
timestamp: November 02, 2020, 01:08:42 pm
content: FWIW I just replaced a couple of wall mounted ethernet sockets this weekend which had been getting increasingly flaky. They would work for weeks and then nothing, plugging and unplugging and wiggling the patch cable would eventually get it going until one completely died. The cause was broken solder joints on the PCB within the socket, it was such a crappy design I binned them and fitted some better quality parts rather than resoldering.The staggered wires in that plug are perfectly normal for flexible patch cables, the I have several here on my desk and they all look like that, though that's not to say you don't have a bad connection in yours.

author: Ian.M
author_rank: Super Contributor
timestamp: November 02, 2020, 01:37:19 pm
content: @Ranayna,I'm not so sure the wire is different colours at the two ends. It could be a photo artifact of the camera white balance, due to different lighting, also dirt from the plaster staining the jacket could be making the socket end look greyer. OTOH if it has got an abomination like the splice you showed us joining patchlead to whatever wire is in the wall its probably FUBARed to the point of needing ripping out and starting over if the O.P. wants a reliable connection at better than 10Mbit/sec.

author: Monkeh
author_rank: Super Contributor
timestamp: November 02, 2020, 02:26:57 pm
content: Quote from: S. Petrukhin on November 02, 2020, 11:32:44 amIt's not bad because you haven't seen it before. The staggering is to allow for larger diameters.QuoteNot only is gigabit not the limit of its capabilities, it's a cat6 cable and jack, and his internet is apparentlyfaster than 100Mbps.Quote from: Ian.M on November 02, 2020, 11:42:32 amKrone LSA contacts are just fine for stranded. Sadly, that one isn't Krone, which is really weird. They're supposed to be. But it's fine, because this isn't stranded..It's a very messy termination on both ends, but assuming it's not jointed somewhere, I'd reterminate at the jack as a first try. Or, actually, replace it rather than try and find the right tool for whatever contact that is.

author: wraper
author_rank: Unknown
timestamp: November 02, 2020, 04:37:42 pm
content: Quote from: Monkeh on November 02, 2020, 02:26:57 pmGigabit ethernet needs regular cat-5e cable and regular connector. You need cat 6 cable only for 10GBASE-T.Quote

author: Monkeh
author_rank: Super Contributor
timestamp: November 02, 2020, 04:45:29 pm
content: Quote from: wraper on November 02, 2020, 04:37:42 pmI.. know that? I'm pointing out that no, gigabit isn't the limit of 5e, and it's not even 5e.

author: andy3055
author_rank: Super Contributor
timestamp: November 02, 2020, 07:37:17 pm
content: st1led,I am looking at picture #2 in your first post. Why are those solid color wires look like they have not been punched down in to that plug properly?All the others with the white stripe seem to be biting in to the wire well but not the Orange, Blue, Green and Brown. I am not sure if the plug is designed that way but all the plugs I have ever crimped, would line them up in one neat row instead of some up/down. I feel the lack of continuity of the Orange wire might be due to that and the others may be just gone in enough to make contact. Looks like a poor crimp job to me.Just a thought.

author: Monkeh
author_rank: Super Contributor
timestamp: November 02, 2020, 07:55:01 pm
content: Quote from: andy3055 on November 02, 2020, 07:37:17 pmAs already discussed, plugs exist which vertically stagger to allow larger diameters. This is one of them - there is physically no way you'd get that pattern in a normal plug.

author: Jwillis
author_rank: Super Contributor
timestamp: November 02, 2020, 11:28:20 pm
content: Quote from: st1led on November 02, 2020, 09:09:28 amI see. Then if its a loose cord in your closet , the break could be anywhere. Is it possible connect a new cord to the old cord and pull it through the wall . If you can replace the cord entirely that might be the simplest solution.

author: Electro Fan
author_rank: Super Contributor
timestamp: November 03, 2020, 03:43:19 pm
content: A systematic approach:Seems like Step 1 one is to confirm which wire is bad. Various tools and techniques are available for this. Step 2 is to figure out approximately where the issue resides - tools and techniques might be available for this too. Step 3 is to determine if you can access the problematic area. If you can access the problem area, Step 4 would then be to address the problem in that area.If you can’t determine where the problem resides or if you can’t reach it then you can consider re-installing the cable on the same path or a different path. If the cable was installed when the structure was built re-installation on the same path or any path may or may not be feasible. (Keep in mind codes and safety.)Next option would be to use a different solution (wifi, coax, ethernet over AC lines, etc.). Cat and coax might be the best for supporting your 750/750 speed (assuming that was meant to be Mbps).Also, as has been mentioned if all the above is impractical you could live with 100 Mbps using fewer wires in the Cat cable.

author: st1led
author_rank: Contributor
timestamp: November 03, 2020, 04:19:38 pm
content: Quote from: Ranayna on November 02, 2020, 10:58:33 amThanks! That was actually the type of connector that was there before I crimped a new RJ45. I tried many times to re-use it, but still wire #2 wasn't connecting. I ended up thinking it was a connector's fault and bought new ones. I didn't find these particularly in the shop, so I might have to search a little bit around. Didn't know it could be an issue to crimp a connector like that I used on a cable with a solid core -- many tutorials on Youtube do it just fine.Care elaborating a little bit on what you mean with these "boxes"? Do you mean wall mounts, or what?

author: st1led
author_rank: Contributor
timestamp: November 03, 2020, 04:30:11 pm
content: Quote from: S. Petrukhin on November 02, 2020, 11:32:44 amThe wires end up on two levels because there is an internal plastic part that arranges cables in two rows (pic attached). I thought it's intended to work in this way.The cable is probably just 5 meters long, it's literally on the other side of the wall.As for gigabit, I have optic fiber at home, up to 750/750 (in the main router). Would be good to get as much in the other rooms!

author: st1led
author_rank: Contributor
timestamp: November 03, 2020, 04:43:58 pm
content: Quote from: Ranayna on November 02, 2020, 01:06:06 pmThe air distance between the wall socket and the cable getting in the router (ending with an RJ45) is less than 4 meters. I have no reason to believe there's such a monstrosity, but of course I can't say for sure, because the cable ends behind a wall-and-floor mounted closet. My best guess is the cable is 5 meters long, not joined anywhere.

author: Ian.M
author_rank: Super Contributor
timestamp: November 03, 2020, 04:45:36 pm
content: First I'd check if the cable in the wall has a broken wire. At the wall jack end, short Orange to White/Orange. Then use a DMM on continuity test at the other (plug) end to check you get a circuit through the Orange and White/Orange wires. If you get continuity, the RJ45 jack's probably bad - replace it and use a proper punchdown tool (https://www.amazon.it/s?k=punch-down+tool&s=price-asc-rank) to terminate the cable to the new one. While you are in there, lightly twist each color-matched pair so the wires stay together right up to the punchdown block, and make sure that the punchdown block terminals 'bite' on a fresh part of each wire, not where the insulation was already mangled.If you don't get continuity, remove the RJ45 plug and test the wires directly. If its still bad, there's a broken wire, possibly where the cable comes out of the wall, but if they mishandled it during installation, the break could be anywhere. Without four good pairs you'll never get gigabit Ethernet, so its replace the cable or live with 100Mbit/sec.

author: st1led
author_rank: Contributor
timestamp: November 03, 2020, 05:03:52 pm
content: Quote from: Jwillis on November 02, 2020, 11:28:20 pmYep, I'm sort of keeping that as the last resort. I'm not even sure I can manage, the cable is loose on the closet side, but on the wall plug side it looks somehow glued to a split wire loom (you see it a bit out of focus in the first picture in the original post.)

author: st1led
author_rank: Contributor
timestamp: November 03, 2020, 05:56:11 pm
content: Quote from: Ian.M on November 03, 2020, 04:45:36 pmGreat idea! So what I did is disconnecting orange and white-orange at both ends: I pulled them out of the PCB on the wall socket, and cut the RJ45 connector open at the other side. Shortened them on the wall side and got a DMM to test the continuity on the closet side. No connection (top of the scale when measuring Ohms). Shortened them on the closet side, tested on the wall side. Same thing.I repeated with white-blue and blue to be sure, which are working. Same for white-blue and white-orange, and blue and white-orange. All the pairs are working, because I get some non-infinite resistance between them.Looks really like this orange wire is broken somewhere in the middle of the cable. I'll do some more testing, but I probably need to replace the whole wire. The end of it towards the closet is loose, but the other one seems to be glued to a wire loom, as I mentioned in another post.

author: Ian.M
author_rank: Super Contributor
timestamp: November 03, 2020, 08:04:27 pm
content: Split the jacket of the cable where it enters the wall in the closet. Spike the orange wire with a thin sewing needle and measure continuity from there to the free end. If you are lucky the break will be in the loose tail and you will be able to cut it off and fit another punchdown type socket. If not, try tugging on the orange wire in the back box of the wall socket. If the break is close to the end of the jacket where the wires are exposed, it will feel stretchy and if you can find the break, you may be able to solder on a length of spare wire, insulate the joint, twist it up with the white/orange wire, and terminate it in the socket's punchdown block.

author: Electro Fan
author_rank: Super Contributor
timestamp: November 03, 2020, 11:55:31 pm
content: Quote from: st1led on November 03, 2020, 05:03:52 pmIt might be worth seeing if there is any indication the cable will pull freely from the end in your photo. If it does, that would be worth pursuing.If the cable seems free (not fully easy to know for sure of course) and the distance through the walls is less than 4 meters it would seem like it might be feasible to pull another cable. Your situation is much better than if you were going up or down to another floor, etc. If you think it's free you could cut off the connectors and check to see if the cable pulls freely; if not you could reconnect. To test (so you don't lose the cable in the walls) securely tie and tape some strong string or the new cable to the old cable and let the old cable pull the string or the new cable from which ever end is easiest to pull (maybe from the end in your photo but you could try in both directions to see if you get any end to end movement). If that works the rest would be easy, just terminate the cable on the junction boxes/jacks and/or add new connectors.I'm guessing it's tacked down or stuck somewhere in between otherwise you would have done this by now but just thought it might be worth testing to see how free or stuck it is. (If you can replace it you might as well go for Cat 6 or better.)

author: st1led
author_rank: Contributor
timestamp: November 09, 2020, 08:36:24 pm
content: Quote from: Electro Fan on November 03, 2020, 11:55:31 pmThank you all for your great support! Unfortunately, I had no luck splitting the cable -- the wire is probably cut somewhere inside the wall. Also had an electrician friend of mine visit me to do some more testing together, just to be reeeally sure. Same thing, orange wire disconnected. I finally decided to replace the whole cable, and will do so within a week or so -- as soon as I get some free time for this new hobby of mine!I will keep you posted on the results.

author: Ian.M
author_rank: Super Contributor
timestamp: November 09, 2020, 08:38:53 pm
content: You did your best . . .