RJ11 cable colour codes

I have a BT master socket on one side of what was an outside wall with the modem on the other side. The hole through the wall isn’t very big so getting a RJ-11 Plug through is difficult. It looked to be no problem, I cut a plug off one end of a lead managed to use a wire mouse and got it through. Then, s**t the colour of the cables is different to the BT instructions on direct wiring. I have Yellow, Green, Red and Black wired on to the other plug as I have seen on other internet sites. But I can’t fine how they equate to the BT cable colours so would be grateful if someone could let me know how they match up.

For an RJ11 to RJ11 cable, the plugs on both ends of the cable should be the same. Can you not see the wire colours in the plug that you cut off?

Sorry I didn't make my self clearer enough, I want to wire it up direct to the master socket not put a plug back on. The instructions at https://www.openreach.co.uk/orpg/home/helpandsupport... show very different colours to those used on the cable I have. It’s which of these I have are used in place of the colours given by BT to directly wire up there master socket not rewire a plug.

The pins the modem needs are the middle two, 3 and 4. If it’s clear plastic you should be able to see the colours, otherwise you’ll need a meter.

Post deleted by 4M2

Thank you does it matter which ones are used, into the BT conexters?

Centre pins and polarity does not matter

Thank you

Hi John

This https://i.pinimg.com/originals/93/0e/2c/930e2c6da031... should make it clear.

(It also explains why cutting a RJ11 plug off a 4-core phone cable and simply trying to crimp on a BT 431A plug replacement without realigning the 4-core cable into the new plug will fail.)

Cheers!

Make sure that RJ11 is suitable cable type for connecting direct to the master - it may be if the wires are not the right type then it won't make a good connection and could cause you issues with the broadband. Personally I would have got a data extension kit that would have allowed you to put an RJ11 socket where the router is and then plug the standard RJ11 cable into that rather than cutting the end of the cable.