RJ45 connection problem or poor contact
kadehach
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brupala Posted messages 111108 Registration date Status Member Last intervention -
brupala Posted messages 111108 Registration date Status Member Last intervention -
Hello, Yesterday the technician came to connect the new fiber optic installation instead of the old VDSL installation.
I put shielded RJ45 connectors on all the cables and when I tried to turn on the box in the living room, it didn't work.
I'm providing a diagram
I put shielded female RJ45 connectors at the ends of the 2 cables (in green on the diagram)
and a male RJ45 cable (in red on the diagram) at the junction box
I connected my box to the fiber box input, it works
I connected my box to the cable at the junction box leading to the fiber box, it works
I made a shunt with 2 female RJ45 connectors on one side female on the other side and connecting them to a male RJ45 cable in the junction box as shown in the diagram
and I went to the living room, connected my box, and it didn't work
My son bought a complete 30-meter RJ45 cable, he tried it directly from the fiber box
in the garage to the living room and it works.
Strange, yet the cable is new and the old installation was connected with this cable with the blue and white wire
I conclude that it is the cable from the junction box in the garage on the left side of the living room that is defective? See the plan
Is the problem due to the cable being cut in the junction box?
On an installation, can a coupler be used to bypass a cut cable?
It’s the only thing I haven’t done yet
It’s a bit annoying because the tiling and painting have been redone
Do you have a solution other than changing the cable? See the diagram if you have an idea
Thank you in advance for any help you can provide
Best regards, Kader
9 answers
Hello,
The diagram... is it done in pairs?
Photos of what you call a junction box would be a plus.
To upload a photo, see: https://www.commentcamarche.net/infos/25913-ccm-inserer-une-image-dans-une-discussion/
Are your RJ45 sockets properly wired for Ethernet (8 wires connected) and not just for telephony (2 wires connected)?
--
It's very difficult to catch a black cat in a dark room.
Especially when it's not there...
The diagram... is it done in pairs?
Photos of what you call a junction box would be a plus.
To upload a photo, see: https://www.commentcamarche.net/infos/25913-ccm-inserer-une-image-dans-une-discussion/
Are your RJ45 sockets properly wired for Ethernet (8 wires connected) and not just for telephony (2 wires connected)?
--
It's very difficult to catch a black cat in a dark room.
Especially when it's not there...
Hello,
it's strange though the cable is new and the old installation was connected with this cable using the blue and white wire you need to check the wiring of the wall sockets, in telephony/ADSL 2 wires (the white/blue in 4/5) are enough. But for Ethernet, all 8 wires of the cable need to be connected.
--
a stranger is a friend you haven't met yet.
it's strange though the cable is new and the old installation was connected with this cable using the blue and white wire you need to check the wiring of the wall sockets, in telephony/ADSL 2 wires (the white/blue in 4/5) are enough. But for Ethernet, all 8 wires of the cable need to be connected.
--
a stranger is a friend you haven't met yet.
Thank you for your quick response, Baladur 13 and Jee Pee.
I connected all the jacks by wiring the 8 wires for each RJ45 jack
according to EIA/TIA 568A standard, but it doesn't work. However, when my son used a 30-meter cable with the connectors, it worked.
There are basic rules regarding cables and connectors. In the walls, we use cables with solid wires that end with female wall sockets. Free cords are cables with stranded wires that have male RJ45 connectors on both ends. Of course, the type of connection at both ends of a cable must be identical.
See: https://forums.commentcamarche.net/forum/affich-37585049-compatibilite-cables-et-prises-rj45
See: https://forums.commentcamarche.net/forum/affich-37585049-compatibilite-cables-et-prises-rj45
Good evening, I put cables in the wall and at the outlet, female RJ45 sockets
The problem I have is at the junction box where the cable is cut
What solution do I have apart from changing this cable?
If I put a shielded coupler between the two cables in the junction box (see diagram)
Will the signal pass?
The problem I have is at the junction box where the cable is cut
What solution do I have apart from changing this cable?
If I put a shielded coupler between the two cables in the junction box (see diagram)
Will the signal pass?
Are the cables inside the walls and with the female RJ45 connectors indeed single-core cables?
In your "junction box," which is not done in networking, if you have 2 female RJ45 sockets, a male/male cord does indeed make the connection. But if you were only using 2 wires before, you need to check all the sockets to see if they too are not partially wired. If the total fiber/box link is less than 100 m, it should work, provided everything is correctly connected.
In your "junction box," which is not done in networking, if you have 2 female RJ45 sockets, a male/male cord does indeed make the connection. But if you were only using 2 wires before, you need to check all the sockets to see if they too are not partially wired. If the total fiber/box link is less than 100 m, it should work, provided everything is correctly connected.
Hi,
your box should already be installed next to the fiber unit (the ONT, I suppose) and the remote TV box connected by your cable(s).
With the long cord you have, you can also test from the "distribution" box to your box, to see which of the two wall cables is faulty since you have two connected end to end.
After that, do a visual check of the wall sockets, and if nothing is detected, test with an RJ45 cable tester.
your box should already be installed next to the fiber unit (the ONT, I suppose) and the remote TV box connected by your cable(s).
With the long cord you have, you can also test from the "distribution" box to your box, to see which of the two wall cables is faulty since you have two connected end to end.
After that, do a visual check of the wall sockets, and if nothing is detected, test with an RJ45 cable tester.
Hello and a big thank you for your answers and for your help
I did the installation at my son's place where the walls are made of multistrand
because when he bought the rolls at Leroy Merlin, he asked the salesman for an installation in the walls, and he was given this multistrand roll. My son knows nothing about it, and neither do I.
When he brought me the roll, I passed the cables from each room (upstairs bedroom) to the living room behind the TV, as well as the one coming from the garage where the technician installed the fiber box (see diagram above)
So I end up with the 3 cables from the bedrooms + the cable coming from the junction box (see diagram) directly behind the wall of the TV in the living room.
In total, I have 4 multistrand cables.
All the cables (4) are connected on one side with shielded female plugs at the living room level behind the TV and on the other side at the bedroom level, I put RJ45 sockets
Brupala my son's box is in his living room with his TV box and all the cables from his bedrooms as well as the cable coming from the garage (see diagram)
For the coupler, I would like to buy the 2
https://www.touslescables.com/b.php?a=A8OL%2Apek%5E1480&c=Voi&h=1826
TLC – Link module, Cat6a, no tool required
But will it work if I buy it?
Otherwise, my son ran a 30-meter RJ45 cord directly from the garage fiber box entry to the box and that works. We passed it through the garden
My problem is at the junction box
There are 2 cables to connect (short-circuit in the junction box)
I tried to connect my box to the cable on the right that goes from the junction box to the fiber box in the garage, and it works, and when I put 2 shielded RJ45 plugs at the ends of the 2 cables in the junction box and tried my box in the living room, it doesn't work
Maybe the cable on the left that goes from the junction box to the living room is defective?
Yet the cable was previously short-circuited in the junction box for ADSL and there was never a problem.
I did the installation at my son's place where the walls are made of multistrand
because when he bought the rolls at Leroy Merlin, he asked the salesman for an installation in the walls, and he was given this multistrand roll. My son knows nothing about it, and neither do I.
When he brought me the roll, I passed the cables from each room (upstairs bedroom) to the living room behind the TV, as well as the one coming from the garage where the technician installed the fiber box (see diagram above)
So I end up with the 3 cables from the bedrooms + the cable coming from the junction box (see diagram) directly behind the wall of the TV in the living room.
In total, I have 4 multistrand cables.
All the cables (4) are connected on one side with shielded female plugs at the living room level behind the TV and on the other side at the bedroom level, I put RJ45 sockets
Brupala my son's box is in his living room with his TV box and all the cables from his bedrooms as well as the cable coming from the garage (see diagram)
For the coupler, I would like to buy the 2
https://www.touslescables.com/b.php?a=A8OL%2Apek%5E1480&c=Voi&h=1826
TLC – Link module, Cat6a, no tool required
But will it work if I buy it?
Otherwise, my son ran a 30-meter RJ45 cord directly from the garage fiber box entry to the box and that works. We passed it through the garden
My problem is at the junction box
There are 2 cables to connect (short-circuit in the junction box)
I tried to connect my box to the cable on the right that goes from the junction box to the fiber box in the garage, and it works, and when I put 2 shielded RJ45 plugs at the ends of the 2 cables in the junction box and tried my box in the living room, it doesn't work
Maybe the cable on the left that goes from the junction box to the living room is defective?
Yet the cable was previously short-circuited in the junction box for ADSL and there was never a problem.
Brupala, my son's box is in his living room with his TV box and all the cables from his rooms, as well as the cable coming from the garage (see diagram).
Do other cables from the rooms also come to the living room?
Oh yes, the small box in the drawing, I didn't understand what it was doing there since its position is odd.
It's a strange setup, everything should come into the garage, that's where the communication cabinet is supposed to be, where the telephone line (VDSL) and the fiber line come in. The fiber should have been installed in the living room too then...
The principle is there:
All your troubles indeed come from using multi-strand cables instead of single-strand cables in wall sockets; there are 4 sockets, so as many chances for bad contact (8 wires per socket, or 32 chances for bad contact).
If the right side works, that's already something, just the left side to redo, but it can also be random; nothing is guaranteed with this setup. Messing around, vibrations, heat, and expansion can turn a dodgy working contact into a bad contact that no longer works.
Are the cables to the rooms also multi-strand?
Do other cables from the rooms also come to the living room?
Oh yes, the small box in the drawing, I didn't understand what it was doing there since its position is odd.
It's a strange setup, everything should come into the garage, that's where the communication cabinet is supposed to be, where the telephone line (VDSL) and the fiber line come in. The fiber should have been installed in the living room too then...
The principle is there:
All your troubles indeed come from using multi-strand cables instead of single-strand cables in wall sockets; there are 4 sockets, so as many chances for bad contact (8 wires per socket, or 32 chances for bad contact).
If the right side works, that's already something, just the left side to redo, but it can also be random; nothing is guaranteed with this setup. Messing around, vibrations, heat, and expansion can turn a dodgy working contact into a bad contact that no longer works.
Are the cables to the rooms also multi-strand?
All sellers are technically incompetent, especially on these subjects, it’s good to know.
To have something reliable, as JeePee told you, it’s better to change the cables, especially since you already have the wall sockets, it would be a shame.
Flexible multi-strand cables are not meant to be embedded in walls, it's the same as in electricity, by the way: No electrician would think of permanently installing flexible wire (the large sections are always multi-strand), flexible cables are reserved for connection cords and extension cords.
To have something reliable, as JeePee told you, it’s better to change the cables, especially since you already have the wall sockets, it would be a shame.
Flexible multi-strand cables are not meant to be embedded in walls, it's the same as in electricity, by the way: No electrician would think of permanently installing flexible wire (the large sections are always multi-strand), flexible cables are reserved for connection cords and extension cords.
Based on experiences on the forum, we can estimate that yes, the cause of the issues is the stranded cable. 4 female RJ45 sockets, 8 ports on each, 32 positions that can cause problems.
See: https://forums.commentcamarche.net/forum/affich-37585049-compatibilite-cables-et-prises-rj45
The self-stripping contacts of the female socket are not designed for stranded wire. The contact is made by slicing the plastic on both sides; if the cable is stranded and it gets crushed, it is possible that no contact is made. For many ports this might still work, but it only takes one for everything to go wrong.
If you read the description of the coupler, it is also indicated for solid wire.
If the cable on the right side of the junction box works, you need to check the 2 sockets on the left section, keeping in mind that on one of the positions the contact is not made or is poor due to the stranded cable. Before, with ADSL you only needed 2 wires out of 8, so 6 positions not validated by ADSL.
See: https://forums.commentcamarche.net/forum/affich-37585049-compatibilite-cables-et-prises-rj45
The self-stripping contacts of the female socket are not designed for stranded wire. The contact is made by slicing the plastic on both sides; if the cable is stranded and it gets crushed, it is possible that no contact is made. For many ports this might still work, but it only takes one for everything to go wrong.
If you read the description of the coupler, it is also indicated for solid wire.
If the cable on the right side of the junction box works, you need to check the 2 sockets on the left section, keeping in mind that on one of the positions the contact is not made or is poor due to the stranded cable. Before, with ADSL you only needed 2 wires out of 8, so 6 positions not validated by ADSL.