Finding short in Cat5e cable

[Jriker1]

I am in the process of cleaning up my cables and as part of it testing all connections. One cat5e wire that snakes thru the walls and I can NOT replace as it's not going to pull around the bends, is showing what seems like a short according to my simple tester. It goes thru wire 1, 2, 3, 4, and then 5 and 6 light up, then when it would be showing 6 5 and 6 flicker and stay lit again, then goes to 7 and 8. This happens with the connectors on either end not plugged into anything. As a matter of fact if I connect the battery powered end of the tester on one end, and don't connect the other end it still does this. I replaced one side of the connector but not the other. Any recommendation on what to do? I have heard there are devices that can literally tell you how far along the cable the short is, but not sure if I would have access to one at the local home depot or what. Thoughts on how to troubleshoot this? Or a different way to wire up the connection to get the most use out of the cable as is?

Thanks.

JR

 

[Cacher_Chick]

A really good cable tester is $750+

I would find another way to fish a new cable,
or switch to wireless.

 

[Sponsor]

 

[Reach4]

Identify which wires are shorted. Measure the resistance between the shorted wires from each end. The resistance will be lower near the short.

http://www.incentre.net/tech-support/other-support/ethernet-cable-color-coding-diagram/ says

You can also see that both the blue and brown wire pairs on pins 4, 5, 7, and 8 are not used in either standard. What you may not realize is that, these same pins 4, 5, 7, and 8 are not used or required in 100BASE-TX as well.
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An RJ45 Ethernet Connector Breakout Board can make taking readings easier. Probing with alligator clips grabbing small sewing needles used as probes is awkward.

 

[Bluebinky]

Like Reach4 said, 10/100/1000 baseT only use two pairs -- just use the good ones.

Gigabit ethernet use all four, I think. Sorry, I'm too lazy to look up the RFC.

 

[Ankhseeker]

They usually reserve the other pairs for PoE or telephone. You could always change/rewire the jacks for the good pair of wires, but the integrity is already compromised and might create a bottle neck if you push too much data through it.

 

[WorthFlorida]

Probably a staple or nail went through the wire somewhere in the wall.