So, a simple job, I thought.

We have some old light switches in the house, thought I’d just replace them with some new ones. The original had 2 wires to the switch, black and red, got some new single one way switches, only 2 wires to put in the back of the switch, did this but now the light is permanently on, the new switch doesn’t turn it off or on, it’s like the feed to the light is constant. Bit confused about this, surely if something was wrong it would trip the fuse box and if I had the wires the wrong way round it would just switch the light on/off the other way around??

Have I got the wrong type of switch? Surely all the switch does is break the circuit to the light??

Can’t do much now as it’s dark, tomorrow I’ll try the wires the other way round, but there’s only 2 terminals on the switch so if this doesn’t work I’m flummoxed!

If you have a single pole switch, must be the switch is knacked . Two wires out and two wires in is simples unless you 2 way switches and you have not used the common for the live.

Is there actually more than two terminals on the switch? Ie, is it not actually switching because you’ve connected them together inadvertently?

Failing that, yes, it’s broke. Got a multimeter?

As thrustyjust says.

Assume you’ve put them one in each terminal (not intending to insult your intelligence but must ask). Switch packaging should say they are one gang one way. If 1 gang, 2 way, put one wire in C and the other in L1 (if marked L1, L2, L3, use L1 and either L2 or L3).

If you’ve another switch, try swopping it.

Rich.

Originally I’d purchased single 2-way switches by mistake, wired this in as per the manufactures wiring instructions but had the same problem, light permanently on, thought this was due to them being 2-way switches so changed them for one-way only, only to have the same problem!

Only 2 terminals on the switch, one at the top, one at the bottom. New switches today, I’ve got a couple more so can try another one in the morning.

Would be a bit odd if both the new 2-way and one-way switch I fitted today were faulty.

Might be worth trying it (carefully!!) without the switch in place at all, see if it’s actually the switch or you’ve shorted something when you’ve disturbed the wiring.

photos?

Ok, I’ll try that in the morning (carefully) although I didn’t need to pull the wires or anything, but you never know …

I’ll try a few things in the morning – remove switch and see if light is still on, change the wires around and a new switch, if no joy I’ll do some photos … thanks for any advice

You haven’t changed the ceiling rose and wired the light cable to black and red and missing the switching live ? , as a mate did that once. Just checking 😉
You can also use 2 way switches. Just use common and 1 and see which way up it switches, as you switch a light switch down for on, unless two way lighting when it can be other way as well and then turn it the right way up to screw on the wall. IYSWIM. When you turn the light on, it goes to common to 1. When you switch it off, then it becomes common to 2.

Did you mess with any wires or just connect like for like?

The 2 cables are will come from the rose. Live and a switched live back to power the lamp.
If there is only 2 terminals at the switch, it’s either knackered (test with a meter) or there is a live/live bridge behind the switch assuming that’s the only thing you’ve touched.
Take switch off and check cables for damage cover bare ends and turn power back on and the light should be off.

Not changed anything other than the switch, basically like for like, no messing with wires. The old switch was quite old but just with 2 terminals, new switch has 2 terminals … doesn’t make sense to me.

Only thing I did do was to pull the wires apart a bit more to be able to get them into the switch, peeling back a bit of the outside plastic casing, old one was side by side, new one has the terminals top and bottom, quite sure this wouldn’t cause a problem.

Was the old casing hard/breaking? Cable could be touching where you pulled them apart,poss causing the insulation to crack further up the cable.

No, wasn’t brittle or breaking, was still flexible, but I’ll check that in the morning too

Is the new switch deeper than the old? Could the wires/terminals be shorting on the box?
Could the exposed wires be long enough to push in from top and bottom to meet in the middle?

here is an idea, but be careful

completely remove switch and ensure wires are separate – then restore power to the circuit

if the lamp lights your fault is elsewhere, otherwise you have some kind of fault with the switch as described above

There’s not a removable bit / screw is there, to turn it in to a 2 way switch…

here is an idea, but be careful

That’s a fantastic idea. Which is why I suggested it six hours ago.

(-:

sorry, having been working on house lights over the summer it is simple once you get your head round it!