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RJ-45 Jack Color Code Sequence
Last updated: 12/18/03

Q. How do I wire RJ-45 jacks so the color code is correct?

I purchsed some wall plugs for my LAN and the companies pattern for the cabling standard is telling me to wire it like this:

green/white green/white orange/white blue/blue/orange/brown/white brown
orange/white orange/white green/white blue/blue/green/brown/white brown

I'm wondering what types of wiring standards these are and if I should just wire like I would a patch cable to keep the wiring consistency?

A. If there is an exact match between the color coding sequence on the back of the jack to the contact sequence on the front, then all of the pairs are backwards, except the orange pair in the first sequence and the green pair in the second sequence.  However, you can't tell if they are in fact correct or not unless you use an ohmmeter to check the back of the jack with the front, or the jack also shows the contact sequence on the back of the jack.  I would assume that what comes out at the front will be correct if you match the color of the wires to the color code on the back of the jack.  That is, I would not connect the white-blue wire to the jack contact labeled blue.  Many jacks have an extra twist, etc. in some of or all of the pairs inside of the jack.

In any event, getting a pair of wires backwards at both ends would still not change the electrical connection characteristics--the electrons couldn't care less.  They do care if two pins that are supposed be connected by a single pair (note pins 3 and 6) are connected by two wires each from separate pairs.  Now, I guess, you are really confused.  So, I suggest that you just blindly match the wires to the color code of your choosing on the back of the jack and use the same code for both ends or the cable.  Larry

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