intermediate switching

[moose]

I am wiring three switches, two existing and one new intermediate switch. Two work correctly, while the new intermediate has no effect.Help please...

 

[ChrisRogers]

ok could i ask how you wired the intermediate?

the common wires (usually red) should be joined using choc bloc or crimped.

 

[moose]

Reds are all joined, a blue and a yellow in both top and bottom, but where does the black go ?

 

[breezer]

have a look in the reference section this forum, shows you how its done

 

[MANDATE]

I don't think the reference section will resolve your problem of the 'black' wire. My initial thoughts were 'what black would this be?'. The strapper cable uses red, yellow and blue, the intermediate switch using the yellow and blue only.
Can I ask how many reds did you join together? and where has the black wire come from.