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I just moved into a house with extensive structured wiring cat 5e and RG6 in each room. The Leviton structured media cabinet only had telephone punchdown bridges, so I got a bunch of Leviton Cat5e data/phone boards and started to identify, label and terminate each cable into a punch board.

Unfortunatley, one cable is totally dead and I'm not sure how / why. Interestingly enough I can hear a tone using a tone tester. But my Lan Tracker shows no lights on any of the 4 pairs of wire in the cable.

My question is, why would I hear a tone using the tone tester but get nuthin using the LAN Tracker? I have tried to re-cut the cable and repunch it to no avail. This is the only cable in the house that is dead.

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2 Answers 2

up vote 14 down vote accepted

The tone generator only sends signals down a pair of cables. You need to send signals down all the pairs - all 4 pairs - to see where the break is. Because most cables are wired to 568B standards, there should be two pair of cable that are unused, and therefore, still viable - which means, you can relocate those strands to replace the damaged ones, and carry on. Simply repunch the cable on both ends with the dead pair swapped out and one of the two spare pairs put in its place, and you're golden.

(Yes, I know that technically you can just replace the one bad wire, but it's easier to remember the color coding scheme when you are working with pairs. And besides, the pairs are twisted, which means if it was a strain relief issue, the twin of the bad wire might also be marginal. That, and if you swap a single out instead of a pair, you defeat the purpose of the twist in the wire - which was to eliminate unwanted signals.)

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"The tone generator only sends signals down a pair of cables." Not knowing anything at all about using a tone generator, I'm curious if the pair used by a tone generator is fixed or if they allow specifying which pair to test? Certainly would make isolating the bad pair(s) easier if you could do that. –  irrational John Jul 21 '10 at 17:16

Does your tone set let you easily check each pair individually?

You might have a wire that got enthusiastically stapled to a stud, and hence is no longer actually made up of as many separate conductors as it should....

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