Couple of days ago my son Ben asked for my help. He bought a house that previously being rented out. Needed extensive upgrade inside and out, and now looks great. The existing porch light didn’t work and nobody before had bothered to fix it. So Ben bought a new one and fitted it but it stayed on and could not switch it off. So I go there with a small tester . First looked at the light switch and what a mess behind the switch panel , even another cable jointed ,nothing to do with the light switches. So screwed that back and decided best way was to tackle the problem from the light end itself. 4 core cable for lighting ??? what the heck, easiest was to disconnect, and test which was what. Using my small voltage tester. Quickly found as to which was live-neutral and earth.
So all he had to do was connect up the right cables in the porch light now he knew which ones.
Oh yes I did help I held the light cover up so he could screw it to the fitting. My strength knows no bounds. 
He is now a happy chappie and can switch the porch light on and off from the entrance hallway
Four core cable is often used for lighting where there are two switches Ie a stair light with a switch at he top and another at the bottom. You need three wires for this plus one for neutral return(Depending on how it is wired and how modern the house wiring).
My front verandah light is wired like this so it can be switched on from inside the house or on the verandah
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I have a question about porch lights (well done RS on fixing your sons light - saved him a few bob I think!) Anyway, my porch light seems to be motion activated, which is fine. But surely once activated, they are meant to stay on unless there is no movement detected for a while? It bothers me that my light goes on and off randomly when I’m outside at night with the dog doing her business. Why doesn’t the light stay on?
PK
Does yours on the sensor back have any contols like these
maybe you have then set for a short duration, One is for length oftime on and the other for when it gets dark to activate the motion detect
It’s a sensor light. They don’t stay on. We just changed ours out for that very reason. I don’t want to go out moving my arms all around to get the light to go on when I want to let our half blind dog out early morning. Good luck.
How’s you new place coming along?
Does your old dog like it?
I haven’t looked at it closely, RS…I’ll do that later on in the daylight. Its just a large square light fitted onto the wall, and operated by a regular switch that I turn on and off. Once its on, that’s when it does the motion lighting thing but doesn’t stay on. I’ll have a look and see if there are any controls.
Exactly…its annoying, and like you say, i don’t want to have to move around just to activate it. When my dog does her business she needs to see where she going (and so do I so I know where to lift it!)
Its coming along slowly, thanks. I still need to decorate and paint, but I have the basics to get along with meantime. John is still getting used to it - I tried to sit in the garden for a while yesterday, but she didn’t enjoy it much, she wanted to get back in the house and her bed 
. Adjusting is hard for her, being a very stressy anxious dog anyway. She’ll get there, its only been a few weeks really. 
you should be able to leave it switched on all the time, the sensor does the switching, I have mine wired without any switches
Ask yourself what good is a motion sensor switched off? if you have an intruder you need the light to come on, it won’t if you have it switched off
In our old house our sensor security light could be turned off by a switch indoors and if you turned it off and back on within a couple of seconds it overrode the sensor and stayed on permanently which was useful if we wanted it as a permanent light when we were sitting outside with friends or for other reasons… Turning it off and on again meant it would return to sensor mode.
Being able to have it turned off meant we could also change the bulb safely.
Most sensor lights have a facility that if you turn them off then on again immediately they stay on permanently until they are turned off again. If you want them to only respond to motion then turn them off and wait 30 seconds before turning them on again.
The waiting time might be different with different brands but that has been the case with all my Arlec ones.
Edit
I see just see Melgal70 has said the same thing our posts over lapped
Thank @Melgal70 and @Bruce I’ll give the switching on and off again when it gets dark later, and see if that works.
@realspeed I don’t have it switched on all the time because I’m trying to be energy conscious with my bills. I have had a look at it and don’t see any controls, and I don’t want to take it off the wall because I’m not sure what I’m doing 
I’ll wait until dark and do the switching on and off to see if that works, I think. I’ll come back here and update.
I just asked my husband about the 4 core cable that Mr Speed’s son had and he said that maybe the original fitting had 4 terminals to allow for both permanent and switched lives in case someone wanted to extend a loop in loop out radial circuit for some reason.
On our current house we bought rechargeable led motion sensor security lights, which work fine for what we need.
It all depends on what you want an outside light for. From what has been posted on here it looks as if some don’t need one with a sensor anyway. For ourselves it protects the back door and gate and even works for the front door the way it is placed. Only issue is the foliage on the trellis framework near it and that has to be kept out of the way.
Do you have any intermediate switches Bruce? I had to give my sparks a refresher course when I bought this place and asked for 2 intermediates due to the long corridor upstairs.
Ours didn’t matter that it was switched on. It was ‘still’ ultra finicky. I’d have to go outside and wave my arms around in a specific way that it was happy with. Sometimes the light would go on, and sometimes it wouldn’t and with a 1/2 deaf, 1/2 blind 16 year old dog, I need to make sure it goes on when I’m putting her out as well as bringing her in. If that’s not the way it was intended to work, then it was malfunctioning.
Now we have a regular nice looking outdoor light that goes on when I need it and does what it’s supposed to do. I’m happy. 
Interestingly or otherwise our back garden light has a sensor for the dark. The problem is that I don’t know where the sensor is. I can turn it off at the mains switch when I need to but you expect to know where the sensor would be. To make matters worse I ought to figure it out - after all I am an electrical engineer!
Painting and decorating is a perfect springtime chore. You can open the windows and air the place out.
It’s great that your dog is still included in your life. She’ll get used to it with time. It’s so cute that she’s already claimed her bed.
Soon you will be doing some gardening and sitting outside to enjoy the outdoors.
I’m very happy for you. 
No, in fact the two switches for my verandah light are about 1 metre apart, either side of the front door. I rarely use the light as there is a street light outside the house, the verandah faces south and is currently home to two fridges, a freezer and a set of bookshelves. The light itself is a 3 foot flourescent tube dating back to Queen Victoria.
Don’t knock the reliable fluorescent batten Bruce. It’s still a long lived good lamp with high light output I deploy 2 x electronic 5fts in my kitchen for shadowless lighting and for good spread I have prismatic diffusers.
Well I tried the flicking on and off thing on my light last night, but it didn’t work. I still had to flail my arms around to make the light go on. Further examination hasn’t revealed any easy way of accessing the wiring, so I might just fix up a “proper” light that stays on when I need it to 
You could just buy a torch. 