The RJ45 connector from the wall of my house is rusted. The copper pins are covered by thick patina. The patina is so thick that it looks black. It definitely reduces communication quality so I would like to change it. The RJ45 cable goes into wall from living room and comes out from bedroom, so it is difficult to replace cable in wall. It is a male socket with patina from wall. The other end is a female socket. I think it is safe to assume the female socket is covered by patina too because they are the same old.The only option is to fix the connector. I think I have two option: remove patina by some chemical or make a new connector. I do a web search and find many accessible patina removerenter image description here. But, they are used to clean art works or antiques, and not a single one lists component and I cannot even start to google if it is poisonous or not for my kid, so I give up. If you know any safe remover I will appreciate. The second way is to make a new one like this video. However, I don't have a RJ45 crimping plier. . The video doesn't show detail of crimping. If crimping only attaches connector to outer layer of cable surface, then theoretically it is possible to make a RJ45 connector without a crimping plier. I just need a glue to attach them. But, if the crimping tool is to push the copper pin into the eight tiny wires to connect, then I don't know how to do it without a crimping plier. And, in fact I don't know how it really works. These two are just my assumption. So, is the any way to fix a RJ45 connector without poison or with common home tools instead of a RJ45 crimping plier? In fact there is maybe still another way. I can cut the cable of a new RJ45 connector and weld it to the old cable. It just looks ugly ,maybe easy to break, and doesn't looks like a good idea.

  • 2
    \$\begingroup\$ If it is the socket which is damaged, you would normally use a punch down tool to insert the wires (being careful to put the wires in the correct places) into the back of the socket. A new socket might even come with a punch down tool suitable for use a few times. \$\endgroup\$ Commented Nov 16, 2020 at 9:54
  • 2
    \$\begingroup\$ Best is to replace the connector but I recently install a new one from scratch and there are some models which do not require a crimping tool at all: just insert the wires in the corresponding colored holes and press a plastic cover which cuts the isolating plastic nicely. No tool needed at all. \$\endgroup\$ Commented Nov 16, 2020 at 9:59
  • \$\begingroup\$ @VerbalKint Thank you very much! crimping-free model is exactly what I need! \$\endgroup\$
    – Superuser
    Commented Nov 17, 2020 at 0:08

1 Answer 1


The best way to go is to cut the cable and put a new connector.

To do so you need a specialized crimping clamp and some connectors. Usually, the way it works is that you insert the cables (without stripping them) and the connector has small blades that will pierce through the insulation while crimping.

Gluing probably won't work or you need some very expensive conductive adhesive.

Trying to remove the patina (oxide layer) also is not so useful as what matters is the connection within the contact.

Trying to solder within the connector will melt the housing.

Given the price of the crimping tool, you definitely rather buy it than cutting/soldering the cables together, it will make your life easier, do a better job and it will be a useful tool to have.

  • 3
    \$\begingroup\$ As I understand, it is the female socket in the wall that is defective. Not the male plug on the cord. Typically, female sockets are not crimped. They have blades which establish connection with the single-core wires of the in-wall cable, when the wires are punched down along those blades. These connector typically don't need specialized tools to be installed: there is a plastic cover with small protrusions that will appropriately push the wires in the blades. You just have to press it firmly and it's done. Basically, OP needs to buy a new $10 socket and install it instead of the old one. \$\endgroup\$
    – dim
    Commented Nov 16, 2020 at 10:03
  • 1
    \$\begingroup\$ Not clear on the question, from what I understood he just has a cable going through the wall given he gave the crimping tool, but it is to confirm. \$\endgroup\$
    – Damien
    Commented Nov 16, 2020 at 10:07
  • 1
    \$\begingroup\$ That might be the case, it is indeed not clear. But according to code, cables that go through the wall aren't supposed to be terminated with male plugs. They are supposed to be terminated with female sockets, and they should go to some patch panel somewhere. Also, they are supposed to be different from RJ45 patch cables (they are solid core, not stranded). So if it is a cable that has been originally installed when the house was built, it is unlikely. If it is a cable that was installed by a DIYer at some point, you may be right. \$\endgroup\$
    – dim
    Commented Nov 16, 2020 at 11:48
  • \$\begingroup\$ Thank you for reminding. It is a male socket with patina from wall. The other end is a female socket. I think it is safe to assume the female socket is covered by patina too because they are the same old. I will update my question about this. \$\endgroup\$
    – Superuser
    Commented Nov 17, 2020 at 0:10
  • \$\begingroup\$ @super picture of both ends? \$\endgroup\$
    – Passerby
    Commented Nov 17, 2020 at 0:25

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.