Errors in replacing a light switch - need some help please

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Good morning, I hope you could guide me to what I have done wrong in replacing a light switch. I have managed to replace all the light switches on my ground floor after redecoration without any issues until I replaced the light switch at the entrance to my front door. This switch controls the hallway light and the outside light, the hallway does have another light switch at the other end that also controls just the hallway light. I have replaced the mentioned switch and now none of the downstairs lights work, it is not tripping out just none of them will work. I have tried multiple configurations and have even tried to put the old switchback how I found it, but I must have made an error somehow. The socket has three lines leading into it, The blue cables and a grey cable are in a terminal block which I did not touch, the other cables are, four brown wires, two black wires with brown sleeves on and one grey cable with a brown sleeve on. The switch has COM L1, L2 at the top and then L1, L2 and COM at the bottom. I have uploaded a pic of the wires and how they are connected. Three brown wires at the bottom are connected to COM and then the single brown wire at the top is connected to the other COM. One black wire with a brown sleeve is connected to L1 at the top, the light grey with Brown sleeve is connected to L1 at the bottom and the final black wire with the brown sleeve is connected to L2 at the bottom.
Swicth Problem.jpg
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It's hard to see what's what from your pic.

When you look inside the switch back box, is it possible to see where all the individual wires go into their respective cable sheaths?

Is there just one three core and earth cable there?

Clearer pictures of the wiring would help decipher the situation.
 
Have you got any voltage testing instruments ?
It's odd that all other lights on the circuit are not working . If you have simply put the conductors into the wrong terminals ,I would expect at least some lights on the circuit would work.
Ensure the blue and grey conductors in the seperate terminal block haven't been accidentally disturbed ,and are all in good contact in the terminal block.
When you replaced the switch PRIOR to the one in your pic ,did you check all was working ,before working on the pictured switch ?
 
I do have a
It's hard to see what's what from your pic.

When you look inside the switch back box, is it possible to see where all the individual wires go into their respective cable sheaths?

Is there just one three core and earth cable there?

Clearer pictures of the wiring would help decipher the situation.

Hi thanks for replying, there are four cable sheaths coming into the back of the box, I will add some more pictures below.
 
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Have you got any voltage testing instruments ?
It's odd that all other lights on the circuit are not working . If you have simply put the conductors into the wrong terminals ,I would expect at least some lights on the circuit would work.
Ensure the blue and grey conductors in the seperate terminal block haven't been accidentally disturbed ,and are all in good contact in the terminal block.
When you replaced the switch PRIOR to the one in your pic ,did you check all was working ,before working on the pictured switch ?

I have a voltage testing instrument, yes. All lights were working fine until I messed around with this switch, I have added some more pictures below.
 

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  • New Socket.jpg
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  • Switch 1.jpg
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I think I have deduced that there are 4 cables into the switch, two twin and earth and two three core and earth. Excluding the earth wires, this would make 10 separate conductors.

Am I right in saying the RH switch is for the hall? In which case, you need to ensure that the conductors in the right hand switch all go back to the same sheath.
 
I think I have deduced that there are 4 cables into the switch, two twin and earth and two three core and earth. Excluding the earth wires, this would make 10 separate conductors.

Am I right in saying the RH switch is for the hall? In which case, you need to ensure that the conductors in the right hand switch all go back to the same sheath.

You are correct yes. the RH switch is for the hallway.
 
Does your outside light have a PIR controlling it?
 
If so, I can't see why your outside light should not come on when the outside light switch is closed.

UNLESS

You have mixed up the conductors in each 3 core and earth cable.

As I said, you need to check that the wires connected to the hall side of the switch are all from the same sheath. You could also check whether the grey wire in the terminal block and the black wire in the L1 terminal connected to the COM with the three browns in also go back to the same sheath.
 
Have you got any voltage testing instruments ?
It's odd that all other lights on the circuit are not working . If you have simply put the conductors into the wrong terminals ,I would expect at least some lights on the circuit would work.
Ensure the blue and grey conductors in the seperate terminal block haven't been accidentally disturbed ,and are all in good contact in the terminal block.
When you replaced the switch PRIOR to the one in your pic ,did you check all was working ,before working on the pictured switch ?

It all seemed fine, everything was working perfectly until I messaged around with this switch, now the kitchen, living room, toilet and living lights will not work (all on the downstairs level)
 
Looking at the pictures again, it seems you have the COMs mixed up.
 
Are your pictures of two different switches?

Its really confusing because it seems you have got pictures of the old switch and the new switch.
 
What voltage tester do you have ,and is there voltages present on any of the conductors ?
 

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