Master socket wiring

[Burnymill]

With FTTP installed and internal 'phone network connected to SH2, I'm fixing an extension socket to replace the Master Socket.  Surprised to find that only 2 wires were connected, orange and blue to screw terminals A and B (green and brown not used).

Externally, I've disconnected the old DIG cable from the junction box, but would  like to keep the remaining section of external cable active in case I want to fix another extension socket at a later date.  Can I connect these two wires into the extension socket, and if so which ones to match up?  I think it may be 2 and 5 but I'm not sure.

[licquorice · Accepted solution]

Not sure why you are replacing the master socket with an extension socket, but yes, terminals 2&5 are correct.

[Burnymill]

Thank you CL, very helpful. The MS is surface mounted and prevents a cupboard door from fully opening - also, the contacts have deteriorated - blue coating - tried plugging 'phone into it but didn't work.
Should have been a very simple job to cut out piece of plasterboard and fit recessed socket - typical, the MS has been placed on top of a baton, so another job more difficult than anticipated!