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 Question by Cameron Clark posted 28 Apr 2004
Added 3rd line to home....telco connected and told me green & white/green was the pair to connect to my punchdown block. (1st line is blue & White/Blue and 2nd line is orange & white/orange). When I connect both sides matching green & white/green to my punch down block..i get nothing. Tried multiple lines with same result. For grins I connected previously working Blue & White/Blue leads to tmy green & white/Green source row and line 3 works. Glad all three lines have dial tone but not sure why that works and why the green & white/green pairs or the orange & white/orange pair will not work when connected to the same row.?
 Answer by Joseph Golan posted 28 Apr 2004
Dear Cameron,
First the telco information is correct as to pair colors and line numbers.

I would need more information to help you find your problem.
What jacks and what type of pin-out was used at the jacks that you are trying to connect to?
Is this a three line telephone or 3 single line telephones?
If it is a three line telephone do multiple line come in on a single jack? if so How many lines/Jack?

Briefly, regarless of the jack type or "normal" wiring, line 1 (white/blue) is always on the center two pins of a jack. if it is a six conductor jack then it is on pins 3 & 4, If it is an 8 conductor jack then it is on pins 4 & 5.

Line 2 now gets a little trickier because there are 3 possible "normal" senarios.
1. 6 conductor jack (RJ-25) 2nd line is on pins 2 & 5
2. 8 conductor jack wired to RJ-61x & T568A line 2 is on pins 3 & 6
3. 8 conductor jack wired at T568B pins 1 & 2 (This one willnot work with most standard telephone equipment.

Line 3 now gets a little worse
1. 6 conductor jack pins 1 & 6
2. 8 conductor jack wired to RJ-61 pins 2 & 7
3. 8 conductor jack wired to T568A pins 1 & 2
4. 8 conductor jack wired to T568B pins 4 & 5

There are numerours sources of these various pinning standards. Check this site for a single source of all these that I have mentioned as well as some additional to see if this helps you sort out your wiring.

If you do post a follow-up question, please address me as "Joe" and the other experts will bypass your question and leave it for me to answer.

Joseph Golan, RCDD

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