How to test and check Home Ethernet Network continuity using a RJ45/RJ11 Cable Tester

Related article on my site: www.shaunchng.c...
Wondered if you home Ethernet wall cabling is up to scratch? Today, I shall go through how to test and check your Home Ethernet points using a rather inexpensive RJ45/RJ11 Cable Tester.
The video introduces you to the device, setup a couple of Ethernet cables before testing the RJ45 wires behind walls. The procedure is similar for all your rooms and testing the RJ11 telephone lines.
The Tester comprise of two parts, a detachable master and remote unit. I got it off Ebay for under $10. It has the model number CPJ20 16T 0318.
It can check for continuity all data wires of any phone or Ethernet cable, including those running behind your home walls. With a cable between the master and remote unit, it sends a signal through all 8 pins of the RJ45 cable to test your cable, patch work or wall plug for any connectivity problems.

[@bmw575]

A+++++++ VIDEO!!!! Thank YOU SO MUCH !!!!! I was at a lost setting up my network at home for fiber. I couldn't understand how to get devices connected through lan to be on the same network as wifi. I had gotten rid of the ISP's Gateway and was using my own router only and I had been stuck for years like this now!!! After watching your video I seen how I needed to have the wall unit not connected to a hub but the router and now all the lan ports are connected and have the 192 ip address instead of 49. this is such a blessing to have found your page. I have done networking before but I couldn't understand what I was doing wrong and never thought about moving the router. Again I really want you thank you so much for helping me out today. I'm definitely a new sub.

[@lilianwiloch]

I have to say this was one great video. You explained things so a novice could understand. Thanks for the help I was needing.

[@springboardtraining]

Exactly the instructions I needed! Thank you, Shaun. Your explanations helped clear some things I had a basic knowledge of.

[@yaelwallace8965]

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[@saulbrysen5125]

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[@yaelwallace8965]

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[@yaelwallace8965]

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[@saulbrysen5125]

@Yael Wallace No problem =)

[@roshantariq2658]

Hi @shaun, Would this method still work if I have to test ethernet cable that had the wall jack on one end and rj45 connector on other side?

[@johnjurena2802]

Yes, most definitely. The RJ45 connector is the same as each end of an ethernet cable. You will need an extra cable to plug into the tester from the wall jack.

[@Blue-Scorpion]

Well explained. I didn't know we can use the tested to test connectivity of the connection in the wall, i thought its only used for "in hand" cable testing. Nice video!

[@junjiewu2165]

Hi Shaun, thank you for the walkthrough. I just recently got my flat and was looking into ways to test the RJ45 ports in the house. Thanks to your video i got some clarifications. Can I check with you, do you happen to chance upon people who uses a LAN switch port in the DB box to split from 1 router port to the various room? Does it reflect the same SSID by doing so?

[@brawas]

I am using this same unit to test the wiring in a building. I notice on a lot of connections 1 doesn't light up, 2 lights up faint, and S doesn't light up on quite a few connections. I then checked both ends and they are crimped / patched properly and the connection works when I connect a laptop. What do you think is going on there?

[@kurtharrington1973]

Thank you very much Shaun! This is exactly the information I was looking for! Much appreciated.

[@garyclayton4765]

Tested a 75 ft cable with my tester and it worked fine. I had new batteries in my tester. Maybe your batteries are weak?

[@sowgelder]

Thanks for the demo. Very informative. It helped me.

[@markrennie7458]

Much easier than reading the horrible instructions that came with the test meter!

[@shaunchng]

Thanks! glad my video is of great help!

[@shihan-gaming]

Instructions? I wish mine came with at least some instructions :-)

[@memeatutube]

It seems it is possible that the continuity test passes and the cable still can’t carry traffic. If the cable was installed 10 years ago, might it have developed defects by now? This cable is over 70 feet long from the router to the den and is not easy to rewire as diy job.

[@hammer_hans]

Can this be used on a patch panel in a server room to the office wall port or would it cause damage?

[@mikelangieri6602]

Shaun... Excellent video, well done. I have one question... is there a way to test signal strength from the gateway to the end of the cable? I have a couple of 75' ethernet cable runs, one to a gigabit switch and one which will go to a Eero 6+ mesh module that will be set up as a bridge?

[@ismecompagny1702]

hello shaun thanks for your instruction video. I have measured a CAT7 cable through a wall socket, but the test box does not give a chronological signal from 1 to 8, but goes from 1 to 7 and back to five. How can I check whether the problem is with the connection in the wall socket or whether the problem is with the connector of the Cat 7 cable?

[@mykylc]

Great instructions. I ordered that same model through Amazon and it lasted about 10 tests...then a couple of LED's burned out.

[@Taras-Nabad]

What does the G led do? The manual says it's supposed to be part of the sequence otherwise you have "bad shield."

[@gmiha]

This video was absolutely perfect. Thank you!

[@Chanok69]

Just bought a cat6 cable and my modem and computer only negotiates 100mbps. The store I bought it from say that there’s nothing wrong with it. I had made to a specific length and now they don’t want to swap it.

[@luigimanis2803]

Hi!how can I test the port of my Lan card integrated on motherboard?The pc don't have any operating system.Thank you!

[@JFV00]

Needed to understand that S state. Thank you a lot.

[@vintess7779]

Shaun, great video! You explained everything clearly and thoroughly. The instructions that I received with the tester, as usual, left much to be desired. They were really useless! Now I am ready to test my connections in my house. Thank you much!

[@evanshakk]

What does it mean when The ethernet tester number light goes reverse from 8 to 1 ?

[@joegenshlea6827]

I had one cable run where no lights 1-8 illuminated at the masters side. What’s going on ?

[@KentuckyRanger]

Excellent explanation on using this tool, thanks!

[@alansmoler8833]

I have the same tester one side I see the lights working from 1 to 8 the remote side is out of sequence however all the lights light up is the cable working properly

[@rushja]

Thanks for doing this video, it's really helpful!

[@nekron75]

What if one connector is malfunctioning (you can't visually see any defect), how do you find out which connector needs to be replaced?

[@jeffvezich8936]

good video can you check the home phone line the same way

[@aussiewozzie1031]

Thank you Shaun , very clear instructions

[@ndrwnbl4571]

So i tried this, but only the master unit was blinking the remote unit wasn't. Why is that?

[@Solid_Nebula]

What if my master side is flashing ground in its cycle? All wires are in the correct order, I’ve painfully made sure of that by checking and recrimping about half a dozen times on each side. But it’s only the master side throwing the ground light

[@9mmsteve]

These DO NOT WORK for any distance beyond about 30ft so BE CAREFUL if using on ANY size home. I wasted numerous connectors thinking I had not connected correctly however it was the TESTER, not the CONNECTION.

[@Teckno77]

I just figured that out the hard way ffs! Lol. Went through about 10 connectors I think my lead is only about 5 or 6 meters long. But getting 7 and 8 saying wrong way round either end just tried the cable and it works perfectly. Now I don't trust these testers at all, not impressed. TO BE CLEAR: I'm talking about the tester I purchased not all network cable checkers in general. Thanks

[@grindererrofficial3755]

@@Teckno77 so you dont trust them coz you are not able to used them properly ? :D So if you going to buy frozen hanburgers, and you will brake your tooth coz its stone frozen, you going to dont trust any hamburgers or frozen meals ? :D LOLGIC

[@Teckno77]

@@grindererrofficial3755Try reading what I actually wrote. I was using it correctly and followed the instructions given with it but I'm also not a bloody mind reader. I don't trust a piece of test gear that gives me FALSE readings which this one does. The lead I made wasn't 15 miles long it was actually around 4 meters long if that after checking. So If it has such a limited distance to which it's accurate then it should be stated clearly on it or stated in documents included with the tester as most test gear that's any good does. I'm a professional electrician so I do have a little experience in these things mate. But you're welcome to your clearly well thought out comment, you have a good one.

[@demguiz944]

Hmm, I have 3 security cameras that are over 50 ft away and this same tester worked fine on all of them. Yours could be defective.

[@Toffie47]

@@Teckno77 If you get the tester saying wrong way around it means you have pins swapped inside the connectors. These testers work perfectly fine well over 150m, if your cable still worked with wrong pins its because some modern hardware has the ability to auto negotiate pin layouts, which is why we no longer need crossover cables for direct connections. Being an electrician will not teach you a single thing about networking, as a network engineer i can assure you of that.

[@jinz9419]

I use it to test and all the lights came on correctly, however, when connecting to my router, it didn't work? Does it have to do with I'm using T568A instead of T568B?

[@MarcusTinBR]

Thank you sir. G had me stumped and you nailed it!

[@MichaelInnes]

4:45 is where he talks about grounding

[@avia4281]

I use a similar tester and tested the cat6. It works but at slow speeds 100mb when in fact it used to work at 700mb up and down. On modem and mobo there is only an orange led meaning a problem. I tested a shorter cable cat 6 and works with green Led (700mb). Do the cables go bad over time? This cable is utc awg32 and went bad I guess over time.

[@luqmanhaider9330]

do you have any idea to check cross over cable check

[@miltonbarbosa390]

Thank you for the instructions, Now I just need a house :)

[@jacksonbodra6450]

Man you so funny. 😁😁😁

[@davidarocha1075]

Great video with easy to follow instructions. Thanks.

[@MASKFORCE]

Awesome. Was looking forward a video on this. Thanks for sharing👍

[@johnisley4578]

Best explanation ever !

[@markw.61]

Nice Shaun. Thanks mate.

[@victorlust9473]

Great explanation and demonstration

[@TetriandochPL]

My tester is not working, the LED is constantly on. LEDs 1 to 8 do not work. Help me :c

[@uuu12343]

Question, is the battery supposed to be flopping around?

[@shaunchng]

The floppy bit is the battery connector, it fits snuggly tight when installed with a battery and inserted into the bay.

[@uuu12343]

@@shaunchng Oh thank you! I realized I had to force the battery into the battery holder

[@AngelusChevalier]

great job on the vid man

[@nikkostiles7134]

Thankyou.. this is a were detailed and well explained video A++++!!!

[@daddydawg1902]

Excellent Instructional Video! Thank you. I'm applying the same technique to testing Telephone cable outlets.

[@bernardacuna2801]

Sir how far the tester could reach?

[@jodicardosa6837]

You saved me.. thanks

[@walterholbrooks673]

Liked your video very much.

[@puneetofficial3]

How to find if there is an issue with which end of the crimping

[@shaunchng]

I would insert both ends of your newly crimped ethernet cable into each end of both test device and run the test. If any of the 8 LEDs do not light up, or in the wrong sequence, you might need to re-crimp your cable.

[@brendanmcmahon6693]

Well done, very thorough

[@georgegeorgel7254]

This tester It’s been out there for long time but not many people knew about it I’ve been using this tester for cables installation for very long time about years ago

[@gabrielcicchi2293]

Great video! Thank you 🙏🏽

[@vamsiismav]

R u a Singaporean?

[@uktay001]

Great clear explanation thank you :)

[@sidekick6119]

Great instructions Thank you 👏

[@johna1857]

Good explanation. Thank you

[@stefanovici88]

thank you very much, lot of useful tips

[@Perplexer1]

Why is nobody testing any S/FTP cables with this tester? Lame. The G is fake on mine. There is not even a LED soldered on the PCB.

[@trakside1]

Great tutorial, thanks this has made is simple to understand & use :-)

[@sampk9229]

excellent informative video , bravo .

[@prithvirajkumar9643]

What if it's skipping LEDs

[@chanhducphung2826]

Thank so much for your great details video

[@InfoVblog]

Great VIDEO

[@there2b]

Thanks!! Recently got one for just $3.

[@bobhatcher5505]

Excellent, thank you!

[@muawizmazlan4684]

What if it skip one number from 6 to 8 and then after 8 came back to 7? This happened to me.

[@DIY_Donkey]

You probably solved it already but it means that on one end pins 7 & 8 are switched around. If its a cable, check the wiring in the plugs to find the offending one, cut it off and fit a new plug. If its a wall plate, open it up and check the wiring and move the wires around on the offending one

[@iainheath3902]

Great video !

[@BCPContractors]

So what if the light in slot 1 doesn't light? But the other 7 do

[@tarahalwes]

You have a problem with the first pin on one or both ends of your cable. It’s possible it wasn’t punched down all the way, or that one wire didn’t get pushed in far enough before the rest were punched down

[@homaabd3054]

Thank you on vedio , i like that

[@Luna-cf3op]

Well explained thanks

[@albanlawrence7637]

Make sure to get good tester or else leds could burn out and it will not light up giving false results

[@romep58]

Awesome video Thanks

[@neelkanthkolambkar8805]

Nice sir

[@ConradoDAsisPC]

[@ryszardjacekrusniak7993]

Incomplete. How about the wrongly installed plugs and receptacles? Disappointed.

[@olisabosah4292]

Thank yoy

[@dhaanbalandhaanbalan3304]

Thank you so much

[@KenACollins]

Flawed demonstration. You proved continuity but you did not demonstrate what the tool displays when you don't have continuity. Because you happened to know that the LV port in the patch panel connects to the Ethernet jack in the living room, you demonstrated that main and remote units light up all 8 LEDs. But when you moved the main unit to the R1 jack in the patch panel, you should have shown us what the main unit and remote unit still plugged into the living room jack display at this point when there is no continuity. Instead, you rushed off and yanked the remove unit out of the living room port before we could see its LEDs and then you just repeated the SAME DEMONSTRATION, this time with R1 and the first bedroom. The whole idea of testing continuity is when you don't know which jack in a room connects to which jack in a patch panel and you are trying to figure this out. Your video did not help me answer this question.

[@erwinsteegen4692]

Thx bro ! N1

[@cliffclavin2503]

These are terrible testers. Very high failure rate. The tester identified a bad cable so I put the continuity meter on it and it passed just fine. If you can't trust the tester then you can't trust the items tested with it.

[@Teckno77]

Can you recommend a suitable alternative that's trusted to work? Thanks

[@ralphcramden606]

@@Teckno77 Any of the Klein tools will do a good job. They are more money but give you more data and are far more reliable. And of course more expensive.

[@Teckno77]

@@ralphcramden606 Thanks, I sometimes need to check Ethernet stuff at work as well so it would be handy.

[@Avalanche2]

Jesus - how many times is he going to explain 8 pins. This could have been a 3 minute video.

[@MechInvent]

Why does a video need to be TWENTY MINUTES LONG. That’s like half a Netflix special.

[@muslimansari1700]

Kitney range jai meter ka

[@SexyRolex]

Thank you