RJ11 cat3 keystone jack wiring

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 Question by mark sampica posted 16 Jan 2006
 RJ11 cat3 keystone jack wiring
Good day;

I am attempting to run cat3 phone wire in my basement. I have keystone jacks and have questions regarding what color wire goes where in the connector. There are 8 wire positions, yet only 6 pins identified. I attempted to wire putting the 4 wires in what I thought was the appropriate slot, but it didn't work (no dial tone). I would really appreciate it if you could tell me what wire goes in #1 slot, #2 slot, #3 slot, #4 slot and so on all the way to #8. The diagram that came with the connector isn't clear (it shows 6 wire colors, but what slots do I put the wire in? Also, can I double up the wires (pass through to another phone jack)?

Thank you for your help!

 Answer by Joseph Golan posted 17 Jan 2006
Dear mark ,

First most jack connection do not accommodate 2 wires on each pin as they are only designed to make a single termination. If you have daisy-chained the wiring, then you must perform a 3-way way splice with the third tail connecting to the jack. Most jacks today are manufactured with the rear connection points able to accept 4 pairs, some jacks though are designed to be RJ-25 (3 pair version of an RJ-11). The color code for these jacks is at this url (look at RJ-25):


As each manufacturer is different your referral to slot 1, slot 2, etc. has no bearing. The color code marked on the side is the hint. Let's look at the first pair which is composed of a White/Blue and a Blue/White combination. When a jack refers to a White/Blue it is looking for either a conductor that is primarily white with a blue stripe or a white conductor that is twisted with a blue conductor. The other half of the pair know as the Blue/White is either a Blue conductor with a white strip or a solid blue conductor that is twisted with a white. The same perception is applied to the other pairs. The conductors must be fully seated in the connector slot and the excess is trimmed off or if this is a true daisy-chain not cut off at all. The primary line for telephone service is on the White-Blue pair, line 2 is normally on the white-orange and line 3 is on the white-green.

To help you a little further, here is a link to an video showing you termination procedure for a Leviton category 5e jack which would be similar to your situation.


The wiring scheme (T568A) is the same for the first two pairs of an RJ-25, the third pair is different but follow the color codes on your jack for the third pair (white-green).

Hope this helps with your problem.

Joseph Golan, RCDD

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