2 way light not working - help please

23 Jan 2007
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United Kingdom
hope someone here will have an idea.
doing a spot of decorating (joy) and just changed a double lightswitch

old switch labeled Top L1, L3, L2 with a red wire in L1+2, and a black with a red collar in L3
Bottom L3,L2,L1 with red to L1 + L2

New Switch Top Common, L1, L2
bottom L2, L1, Common

i put all the L1 and L2 back in the correct places, and the L3 into the top common, now 1 switch turns one light off, and the other on, the other switch does nothing
changing the L3 (black with red collar) to the bottom common gives nothing.
landing light operated by this switch and another at top ot the stairs. this switch also operates a hall light. all worked with the old switch, just noticed it says 'double' not '2 way' on the new fitting.

Advice welcome (so long as it doesn't involve putting old switch back on, or calling a sparky).

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Also, the switches are not normally arranged with their terminals top and bottom - they are normally arranged in a triangle, such that L1 at the top corresponds to L2 and L3 at the bottom, and L1 at the bottom corresponds to L2 and L3 at the top.
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not the actual solution to yours, but shown how the switches are usually arranged..

not sorted mine out yet, need the light and if it all goes wrong...
that diagram shows 8 wires, i have just 5
2 appear permament live (multimeter for xmas), one of which is, i guess, the common (single)
should i branch (spur?) across from this common to the other?
was it linked before? if not then no..

they might be off 2 seperate circuits as it's a hall light and one is almost definitely 2 way switching..

I did say that's not the solution to your problem, it was done for another answer, but the picture shows the grouping of terminals for each switch..

the live from upstairs will go into COM..
what used to go in L2 will now go in L1..
what used to go in L3 will now go in L2...

the red and black cable will more than likely be the hall light, not the landing light..

you should have a red and black T+E cable, a twin red T+E cable, and a single cable..

if you can post a photo of the cables in the box then we might be able to tell you what goes where
you should have a red and black T+E cable, a twin red T+E cable, and a single cable..

absolutely right, shielding only just comes into the backplate, tried taking a photo, camera's doing a very bad job.
i have discovered that wrapping post-it-note sticky round the cable and labelling isn't a long term solution, as all the labels have fallen off.no £ to pay a sparky, so i'm gonna have to get it done.

present situation is (i'm going to play some more soon) both lights come on and off if i have the landing light switch on (down),
on the double 1st switch up turns on hall light, 2nd switch down turns on landing
the landing is 2 way switching, the hall 1 way.

going to have a coffee and hang another sheet of paper before tackling again
done it now, thanks. bit of continuity testing and trial and error to get everything to work as it should (down-on)

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