Question Ethernet Cable Disconnection

Nov 3, 2019
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Hey, recently ran a new Ethernet cable from from of workshop to the back (easily 40-50 meters), ive used a cat 6 cable with fj45 connectors.
From there its plugged into an internet switch.
Which diverts to my room, Basically i can use the internet perfectly for a time before it randomly stops working. I can unplug and plug it in again on either end and itll start working again before the same issue happens.
The first time i unplugged it from the modem and it worked. The second time that did nothing so i did it at the switch and it worked again. The internet will last an hour or two before stopping and saying theres no cable connected.
 

LWFG001

Commendable
Apr 12, 2017
150
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1,615
The length is OK for a regular Cat 6 copper cable at 10/100/1000 ethernet/fast_ethernet/gigabyte_ethernet speeds.

First thing I'd do would be to plug the cable into another port on the switch. Ports on switches can deteriorate. I'd also shut the switch off and turn it back on to reinitialize the switch.

Next, I'd look at each end to see if the ends are plugged in fully to the switch on one side with a green light for the port showing and on the other end a green light showing on the back of the network card on the computer.

It's also a good idea at this point to check the cable run to see that some portion of the cable is not lying across fluorescent lights or on or near anything that can cause electrical magnetic interference (EMI) such as a power transformer.

If the lights are green on both ends and the cable is not lying on or near anything EMI that can scramble data or cause connection drops, then I would test the cable with a network cable RJ45 tester.

See, the light on each end can be green for awhile and then change. So to be sure, you test the cable. This will test to see if all eight wires in the cable are working and if the cable is attached to the RJ45 connector properly. Amazon sells this one cheap for about $10.00:

View: https://youtu.be/3tHvOLBp2zM


If the cable checks out, then something else is happening and at that point you normally start taking a closer look at the switch (which you should already have turned off then back on after plugging the cable into a different port on the switch), the network card, and the configuration settings. However, VERY often in your situation the cable does NOT check out.
 
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Nov 3, 2019
15
2
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The length is OK for a regular Cat 6 copper cable at 10/100/1000 ethernet/fast_ethernet/gigabyte_ethernet speeds.

First thing I'd do would be to plug the cable into another port on the switch. Ports on switches can deteriorate. I'd also shut the switch off and turn it back on to reinitialize the switch.

Next, I'd look at each end to see if the ends are plugged in fully to the switch on one side with a green light for the port showing and on the other end a green light showing on the back of the network card on the computer.

It's also a good idea at this point to check the cable run to see that some portion of the cable is not lying across fluorescent lights or on or near anything that can cause electrical magnetic interference (EMI) such as a power transformer.

If the lights are green on both ends and the cable is not lying on or near anything EMI that can scramble data or cause connection drops, then I would test the cable with a network cable RJ45 tester.

See, the light on each end can be green for awhile and then change. So to be sure, you test the cable. This will test to see if all eight wires in the cable are working and if the cable is attached to the RJ45 connector properly. Amazon sells this one cheap for about $10.00:

View: https://youtu.be/3tHvOLBp2zM


If the cable checks out, then something else is happening and at that point you normally start taking a closer look at the switch (which you should already have turned off then back on after plugging the cable into a different port on the switch), the network card, and the configuration settings. However, VERY often in your situation the cable does NOT check out.

I appreciate the fast response, ive checked the cable and its not laying on anything that can cause issues i believe, i made sure even when i ran it. I switched ports as well, but that does nothing as it wont connect now. The switch and cable is brand new, the lights on switch are all green but the cabled side plugged into the modem will now not light up at all.

Ill buy the tester to test the cables, does that mean theres a kink causing it to stop working or could it just be the connections of the RJ45 heads? if so what can i do to fix them? Can post photos if need be, cheers appreciate the help
 
Be sure the cable is not a fake ethernet cable. Ethernet cable must be pure copper (no cca) and must have wire size 22-24. None of that flat or thin cable. Since this fake cable is not actually certified it is hard to predict how well it will work. It has massive issues the longer the cable is
 

LWFG001

Commendable
Apr 12, 2017
150
8
1,615
I appreciate the fast response, ive checked the cable and its not laying on anything that can cause issues i believe, i made sure even when i ran it. I switched ports as well, but that does nothing as it wont connect now. The switch and cable is brand new, the lights on switch are all green but the cabled side plugged into the modem will now not light up at all.

Ill buy the tester to test the cables, does that mean theres a kink causing it to stop working or could it just be the connections of the RJ45 heads? if so what can i do to fix them? Can post photos if need be, cheers appreciate the help

It's always good to have a $10.00 cable tester lying around that you know how to use correctly ;).

OK, so the cable is plugged into the switch and the port light on the switch the cable is plugged into is green. Assuming you left the switch plugged into the router or modem, whichever you have, that side should be good.

Yet I need to ask a question about your switch. You said the lights on the switch are all green. Do you mean only the ports that have cables plugged into them? Or do you mean all of the port lights on the switch are green even ports which do not have a cable plugged into them? What brand and model is the switch?

Moving along... the other end of the cable is plugged into the back of the computer and the network card's light is off. That's a problem. Until the network card light on the computer is green when the cable is plugged into it, you won't be able to access the network from that computer.

Here's what the green light on a generic network card looks like when you plug an Ethernet cable into it and it is working correctly:

ibxwim02293550.jpg


Whether that computer uses an onboard network port on the computer's motherboard or a network card like the one shown in the picture that's plugged into the computer's motherboard: The green light should be on next to the cable plugged into the back of your computer.

So your problem is either the cable not working, the network card not working, or the switch has some issue going on. Answer my questions in green about the switch and provide me the switch information. Then, test the cable to make sure it's good. If the switch is configured correctly and the cable tests good, then it's the network card.
 
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LWFG001

Commendable
Apr 12, 2017
150
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1,615
Also, I just caught this. You said "the cabled side plugged into the modem." By modem, do you mean the back of the computer? Or, do you mean you have some kind of a ethernet modem next to your computer far from the switch? I'm confused by this statement.

Normally, one end of the cable plugs into a switch or router or modem and the other end plugs into your computer.

But you posted that one end of the cable is plugged into the switch and the other end into a modem. Was that a typo?

Can you draw a diagram of your network?
 
Nov 3, 2019
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Also, I just caught this. You said "the cabled side plugged into the modem." By modem, do you mean the back of the computer? Or, do you mean you have some kind of a ethernet modem next to your computer far from the switch? I'm confused by this statement.

Normally, one end of the cable plugs into a switch or router or modem and the other end plugs into your computer.

But you posted that one end of the cable is plugged into the switch and the other end into a modem. Was that a typo?

Can you draw a diagram of your network?

View: https://imgur.com/a/GUkxvCV
diagram attached here along with photos of the ports of the switch

So basically on the switch only the two ports that are plugged in are lit, while on the modem where it originates is not lit.

basically ive been testing it with my ps4 which is only 4 weeks old which says no lan cable is connected, while my pc doesnt detect it.
 
Nov 3, 2019
15
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Be sure the cable is not a fake ethernet cable. Ethernet cable must be pure copper (no cca) and must have wire size 22-24. None of that flat or thin cable. Since this fake cable is not actually certified it is hard to predict how well it will work. It has massive issues the longer the cable is

I dont think its fake, bought it from bunnings a massive company and its quite thick
 

LWFG001

Commendable
Apr 12, 2017
150
8
1,615
Thank you AAAii, that diagram cleared everything up! I see you have the switch connected to the modem and your PC connected to the switch. That's exactly how it should be.

But you are saying that the end of the long cable, which is plugged into the modem, is not triggering the port light on the modem to light up.

Yet, the PS4 works off the short cable connected to the switch while the PC does not work off the same short cable connected to the switch. Is this correct?

Also, is it possible to upload a picture of the modem (which should be powered on) showing the side the long cable plugs into while the long cable is plugged into the modem?

And carefully do the cable test and do the testing more than once to be sure. Refer to my previous post with the video if needed. It's important to follow the cable tester instructions and check each wire carefully. And to do it multiple times. If even one wire is faulty, we need to know that. Let us know the testing results.
 
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Nov 3, 2019
15
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Thank you AAAii, that diagram cleared everything up! I see you have the switch connected to the modem and your PC connected to the switch. That's exactly how it should be.

But you are saying that the end of the long cable, which is plugged into the modem, is not triggering the port light on the modem to light up.

Yet, the PS4 works off the short cable connected to the switch while the PC does not work off the same short cable connected to the switch. Is this correct?

Also, is it possible to upload a picture of the modem (which should be powered on) showing the side the long cable plugs into while the long cable is plugged into the modem?

And carefully do the cable test and do the testing more than once to be sure. Refer to my previous post with the video if needed. It's important to follow the cable tester instructions and check each wire carefully. And to do it multiple times. If even one wire is faulty, we need to know that. Let us know the testing results.

View: https://imgur.com/a/GUkxvCV?


New photos attached, basically the long cable is not lit on the modem side, and the short cable does not light up on the pc side although they both light up in the switch. Sorry for being a little unclear. neither the ps4 or pc work as they are both unable to detect the ethernet cable. Ill buy the tester today after work and get it checked out!
thanks once again
 
Nov 3, 2019
15
2
15
View: https://imgur.com/a/GUkxvCV?


New photos attached, basically the long cable is not lit on the modem side, and the short cable does not light up on the pc side although they both light up in the switch. Sorry for being a little unclear. neither the ps4 or pc work as they are both unable to detect the ethernet cable. Ill buy the tester today after work and get it checked out!
thanks once again
if you need any more photos just let me know! thanks!
 

LWFG001

Commendable
Apr 12, 2017
150
8
1,615
On the modem side its plugged into LAN 1

Look at the picture, no green light on LAN 1. It should be green. You'll have no network or Internet access from your computer and PS4 until the problem is identified and resolved and the LAN 1 green light comes on with the long cable plugged into it.

To recap, you have already tried plugging that end of the long cable into another one of the LAN ports on the modem and the green light did not come on though the other end of the long cable is plugged into the switch and that port light is green.

Of course, let me know when the cable has been correctly tested and what the testing results are. If one or more wires do not test out, the cable is the problem.

---> But in the meanwhile please, if you can, plug the cable in LAN 2 (where the green light is on) into the LAN 1 port to see if the LAN 1 green light comes on. You can then plug that cable right back into the LAN 2 port where you got it from when you're finished.

Let me know if the LAN 1 port light comes on when you plug the cable that's in the LAN 2 port into the LAN 1 port temporarily to check that.



P.S. Don't worry about the green light on the computer network card not coming on, now that we know the long cable is not working with the modem it should be off at this point. That's normal.
 
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Nov 3, 2019
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Look at the picture, no green light on LAN 1. It should be green. You'll have no network or Internet access from your computer and PS4 until the problem is identified and resolved and the LAN 1 green light comes on with the long cable plugged into it.

To recap, you have already tried plugging that end of the long cable into another one of the LAN ports on the modem and the green light did not come on though the other end of the long cable is plugged into the switch and that port light is green.

Of course, let me know when the cable has been correctly tested and what the testing results are. If one or more wires do not test out, the cable is the problem.

---> But in the meanwhile please, if you can, plug the cable in LAN 2 (where the green light is on) into the LAN 1 port to see if the LAN 1 green light comes on. You can then plug that cable right back into the LAN 2 port where you got it from when you're finished.

Let me know if the LAN 1 port light comes on when you plug the cable that's in the LAN 2 port into the LAN 1 port temporarily to check that.



P.S. Don't worry about the green light on the computer network card not coming on, now that we know the long cable is not working with the modem it should be off at this point. That's normal.
View: https://imgur.com/a/GUkxvCV?


New photos attached, basically the long cable is not lit on the modem side, and the short cable does not light up on the pc side although they both light up in the switch. Sorry for being a little unclear. neither the ps4 or pc work as they are both unable to detect the ethernet cable. Ill buy the tester today after work and get it checked out!
thanks once again
if you need any more photos just let me know!

Just tested the cable out wire 3 gets skipped on the network tester, meaning I damaged the cable with a kink when i ran it unfortunately thanks for the help, looks like im going to have to run a new cable
 

LWFG001

Commendable
Apr 12, 2017
150
8
1,615
if you need any more photos just let me know!

Just tested the cable out wire 3 gets skipped on the network tester, meaning I damaged the cable with a kink when i ran it unfortunately thanks for the help, looks like im going to have to run a new cable

BINGO! The long cable is bad and needs to be replaced. Good job working through it to the end and glad I could help. Thanks for letting us know.
 
Nov 3, 2019
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BINGO! The long cable is bad and needs to be replaced. Good job working through it to the end and glad I could help. Thanks for letting us know.

Basically ran a new wire today and tested both cables, both fully functional, i played for an hour but then disconnected? and cant detect it anymore and neither will my pc lan port light up. i tested the short cable at the switch side with just the big tester while the other side was plugged into the ps4. Im unsure why its not detecting anymore. The long cable is lit on both ends and tested perfectly. Both ps4 and pc cant detect is there any reason why?
 
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LWFG001

Commendable
Apr 12, 2017
150
8
1,615
Basically ran a new wire today and tested both cables, both fully functional, i played for an hour but then disconnected? and cant detect it anymore and neither will my pc lan port light up. i tested the short cable at the switch side with just the big tester while the other side was plugged into the ps4. Im unsure why its not detecting anymore. The long cable is lit on both ends and tested perfectly. Both ps4 and pc cant detect is there any reason why?

You solved the long cable problem, both ends light up their respective devices. The modem port light is green and the switch port light is green. You have internet connectivity from the modem to the switch. Good job! Leave the long cable alone, it's fixed.

But now you've uncovered a second problem preventing connectivity from the 5-port switch to your PC and PS4.

The goal now is to get the short cable to light the switch port light on one end and the PC network card light on the other end. In order to get those lights on, you have to have a good connection over the short cable from the switch to the PC.

Use the cable tester correctly on the short cable. One end of the cable tester will go on an end of the short cable and the other end of the cable tester will go on the other end of the short cable. Run the test and see if all 8 wires test good or not. What is the result of a correct testing of the short cable with the cable tester?

Also, the problem may be as simple as the end of the short cable that plugs into the PC is going into the wrong network card. See, PC computers often have TWO network cards with one of them disabled. So if you plug the short cable into the disabled network card the lights won't come on and it won't work.

Look carefully at the back of your PC computer. How many ports on the back of the PC computer can you plug that short cable into? Take a picture of the back of your computer so we can see it.
 
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Nov 3, 2019
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I appreciate the help once again, so basically ive discovered the source of the problem (sort of) the modem side where the long cable is plugged in is no longer lit. All though both cables are testing perfectly. Could it possibly be bad crimping? ive changed the port it was plugged into though there was no change. I believe thats why the short cable is no longer being detected. Sorry for the back and forth!
 

LWFG001

Commendable
Apr 12, 2017
150
8
1,615
I appreciate the help once again, so basically ive discovered the source of the problem (sort of) the modem side where the long cable is plugged in is no longer lit. All though both cables are testing perfectly. Could it possibly be bad crimping? ive changed the port it was plugged into though there was no change. I believe thats why the short cable is no longer being detected. Sorry for the back and forth!

If the cable tests perfectly, it's not the cable in my experience. First, I usually power off and then power on the modem to see if the connection is restored. Modems take a few minutes to come up so be patient. If it's fixed, great. If not, I call the Internet service provider who gave me the modem and ask them to perform tests to the modem to check it and see if it's working correctly.
 
Nov 3, 2019
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If the cable tests perfectly, it's not the cable in my experience. First, I usually power off and then power on the modem to see if the connection is restored. Modems take a few minutes to come up so be patient. If it's fixed, great. If not, I call the Internet service provider who gave me the modem and ask them to perform tests to the modem to check it and see if it's working correctly.

Alright that makes sense, thanks once again ill see what i can do!
 
Nov 3, 2019
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Alright that makes sense, thanks once again ill see what i can do!

Update, called company no issues on their ended.
connected switch next to modem to test it and it works fine.
contacted an IT guy who came an inspected it and he found no faults.
Cables are all testing good.
BUT on the modem side the long cable is still not being detected so therefore no internet. He recommended trimming the cat 6 cable down to see if it helps because it may be too long (58-60m) or to place a switch mid way! at a loss as what i should do!
 
Etherenet cable can go 100m. BUT again be sure the cable is pure copper and not CCA.

Recheck your wire pairs very carefully so you have the correct color pattern. The cheap cable testers only make sure the wires connect end to end they can not detect improper wire colors. If you for example put orange in pin1 and brown in pin 2 on both end it will test fine but never work. Follow 568a or 568b colors on both ends.
It could also be a wire just barely is crimped but not good enough. Unfortunately the meters that can test all this cost more than home users are willing to pay.

I normally recommend using keystone jacks rather than crimp on rj45 plugs for permanent installs. They cost more money and you need short patch cables but they are much simpler for a new person to get correct, They have a wire color on the jack and you can do 1 wire at a time rather than all 8.
 
Nov 3, 2019
15
2
15
Etherenet cable can go 100m. BUT again be sure the cable is pure copper and not CCA.

Recheck your wire pairs very carefully so you have the correct color pattern. The cheap cable testers only make sure the wires connect end to end they can not detect improper wire colors. If you for example put orange in pin1 and brown in pin 2 on both end it will test fine but never work. Follow 568a or 568b colors on both ends.
It could also be a wire just barely is crimped but not good enough. Unfortunately the meters that can test all this cost more than home users are willing to pay.

I normally recommend using keystone jacks rather than crimp on rj45 plugs for permanent installs. They cost more money and you need short patch cables but they are much simpler for a new person to get correct, They have a wire color on the jack and you can do 1 wire at a time rather than all 8.

I have checked them multiple times and so did the technician the colours are wired correctly. I have no issue getting the jacks but id rather make sure it works first before wasting time and money. Ive wired other cables for friends with no issues using them. So quite annoying, all my connections are orange white, orange, green white, blue, blue white, green, brown white, brown it could possibly be a weak crimping for all i know so i will crimp them again on both ends.