CAT5 Wiring FREE cabling and networking Helpdesk
 Question by GIAO PHAN posted 27 Apr 2005
 CAT5 Wiring
have the house prewired with Ethernet cabling. I terminated both side of the CAT5 cables using T568B (all 8 wires). I placed the DSL modem and a router at the panel where all the CAT5 cables are routed to. At the wall RJ45 jacks, I got Ethernet signal if the jumper cable is 2-pair straight through but do not get any signal if the jumper cable is 4-pair straight through. The same 4-pair jumper cable work if I connected it directly from the router to a laptop so I know there is not any problem with the 4-pair cable.

I don't think the CAT5 cables are tested after installing.

The 2-pair cable came with the router that I bought. The color is 1-white/orange, 2-orange, 3-white/blue, 6-blue.

The 4-pair cable came with the DSL modem and it is wired to T568B. That where I learned the pin out. Later I found out that is called T568B from your website.

Please let me know if you need any more info.
 Answer by Joseph Golan posted 28 Apr 2005
Dear GIAO,

It almost sounds like there is a problem with one of the un-used pairs (1 & 4) is crossed with one of the required pairs (2 & 3) for ethernet services. This would explain why the 2 pair cable works, because it is isolated from the unused pairs. The installer who did the category 5 outlet cables should have provided you test results for each run, if not, you are going to have these cables tested to cat 5e parameter to insure that the problem is not in the cable.

Joseph Golan, RCDD

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