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Cat 5 Wiring issues...? Wha'd I do wrong?

Cat 5 Wiring issues...? Wha'd I do wrong?

Cat 5 Wiring issues...? Wha'd I do wrong?


Been working on setting up a WAN, within a LAN via a Linksys Etherfast DSL Router.
Installed the wall jacks as following (per instructions).

Cat 5 color-------wall jack color.

connections have been checked and via my voltage meter that I used as a probe to make sure the other end of the Cat 5 wire in my "tek-room" were active.

I also crimped my own wires, (the other end of the wall jacks)that go into the router as follows...."twisted Straight-Through"

Pin 1- orange/white  Pin 5- blue/white
Pin 2- Orange        Pin 6- green
pin 3- Green/white   Pin 7- brown/white
pin 4- Blue          Pin 8- brown

Seeing this was my first time crimping I also made sure that they were snug and proper. Took me a few tries but I'm confident with them now.

Oh ya....my problem...almost forgot .)

When I plug them into the router I get no LED Link/Act activity or light what so ever. Cause...unknown...
Must be the wall jacks, perhaps I wired them wrong, I used the color scheme that the back of the wall plate package suggested.

Anyhow, I should also mention that the router works well, Im using it now, thing is its in  the middle of the office floor connecting 4 pc's in a very unorthodox setting, straight from the Pc's ethernet card to the Router...All works but its an ugly situation let me assure you!

SO...any of your suggestions would help and if i left something out, (like this isn't long enough)please let me know!!

Have Yourselves a great New Years and thanks

Josh Maxwell
Discover Computers

RE: Cat 5 Wiring issues...? Wha'd I do wrong?

Well, there are a few things that can go wrong here.  First, are you using stranded or solid wire?  Second, are you connectors ALL stranded or solid?

I am going to assume all are solid.

The quality of the RJ-45 plug is important.  Did you use AMP or an unknown brand?  The cheaper brands do not straddle (solid) or pierce (stranded) the cable as well.

Did you use a cheaper "side" crimper or AMP ratcheting crimper.

Last and most important, do you see copper shining through the end of the connector?  Each wire needs to butt-up to the end of the RJ-45 plug.  If you cant tell, turn the connector upside down and see if the wire appears to go to the end.

The RJ-45 is usually the culprit.


RE: Cat 5 Wiring issues...? Wha'd I do wrong?

One other thing is what is the linksys plugging into? a hub or switch? if so, then you need a crossover cable.. You need to flip the pairs. This would give the symptoms you describe..

Just a thought


Find me at www.packetattack.com

"The trouble with giving up civil rights is that you never get them back"

RE: Cat 5 Wiring issues...? Wha'd I do wrong?

Two things:

The reason the link light does not come on is almost always because of a wiring screw-up. Somewhere you don't have continuity on pairs 2 and 3. Pair 2 is on pins 3&6 and pair 3 is on pins 1&2. These pin designations refer to a RJ-45 plug held in your hand with the wire down and the pins up, count from left to right OR a wall jack mounted with the pins on top and the latch down. I always advise getting or building a basic continuity tester if you will be doing any wiring at ALL. My favorite inexpensive tester is a www.milestek.com Uni-Network Test Kit 40-30089 at $79. Before you complain about the price figure the number of hours you have spent on this problem and your hourly rate.

The wall jacks you describe with the red, green, yellow, black... wires are most likley designed for telephone use and not CAT5 compliant. Even if they are not CAT5 compliant the link light should still come on if you have continuity on pairs 2 and 3.

Best of luck!

RE: Cat 5 Wiring issues...? Wha'd I do wrong?

Thanks all!

I figured it out!
Took apart that wall jack, followed what colors went with each pin and matched it with the proper color code of a striaght through Cat5.
Continuity is what was the proplem!\
Hope you all had a great new years!@

Josh Maxwell
Discover Computers

RE: Cat 5 Wiring issues...? Wha'd I do wrong?

I recently tried changing my setup from an assigned  by cable co.second ip address with hub to single ip with router. Wiring is unchanged. Don't know what's wrong but now computer 1 is slow as dirt, and computer 2 is not getting connection at all. Odd thing, to get the hub to work, I had to engage the "uplink" button. Is my problem  due to possible miswiring at connectors? Could one or both be "crossover" instead of "straight through"? Is "straight through" the proper wiring to use? What about the patch between the modem and the router?  

RE: Cat 5 Wiring issues...? Wha'd I do wrong?

Colors mismatched @ the wall jack.


The important sets are the BLUE/BLUE-White and the GREEN/GREEN-white pairs.  These are pairs 1&3.  They are where everything takes place in 10BaseT.

What you've done is split pair 3.

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