Just been reading the latest copy of the highway code (what a sad life I lead) and spotted this:
You MUST
- ensure all sidelights and rear registration plate lights are lit between sunset and sunrise
* use headlights at night, except on a road which has lit street lighting. These roads are generally restricted to a speed limit of 30 mph (48 km/h) unless otherwise specified
- use headlights when visibility is seriously reduced (see Rule 226)
Night (the hours of darkness) is defined as the period between half an hour after sunset and half an hour before sunrise).
[Laws RVLR regs 3, 24, & 25, (In Scotland - RTRA 1984 sect 82 (as amended by NRSWA, para 59 of sched 
)]
According to this you can legally switch off your headlights and drive around if there are street lights on. Unless I’m reading it wrongly.
You do read it right.
In a lit 30 zone, you can run on sidelights. I’d not recommend it myself.
If the streetlights are out, or the limit goes up beyond 30. then you must have dips on.
Just go with the safe option, dips from 30 mins before dusk to 30 mins after dawn.
I think of sidelights more as parking lights.
If the vehicle is rolling, it’s dipped headlights for me.
See and BE SEEN.
I turn my lights on when I feel its time to. None of this 30 mins before or after, if I think they should be on at 2 in the afternoon then they are.
What everyone else says…you can drive on sidelights in 30mph zones, but if you have a crash, it will be taken by the police as a possible contributory factor.
For me, it’s safety, safety, safety all the way! I often drive on dipped headlights when it’s bright sunlight too as it makes you more visible to other road users. I do that in the car as well.
You get a lot of people driving on side lights in rain/fog - might as well not bother at all because you can hardly see them. I would only use my side lights when parked at the side of the road at night. They’re not much use for anything else in my opinion.
I don’t want to grumble on british drivers, but for me that driving on parking lights is some kind of disaster. Even when it’s heavy raining plenty of drivers still drivers with no lights at all!
I have in my car (british one) four opportunities: parking lights, which are turning to daylights, when I switch the ignnition on, then short beam and main beam.
Maybe it was popular in british cars before, and people are used to that when they drive, parking lights are switching for daylights? I don’t know, just asking.
But I think, that it could be much better with lights in britain.
I remember one day I was leaving lay-bay during really heavy shower and I seen other lorry changing lane and flashing on me to give me a way. So i pulled on the main carriageway and then it turned that there is another vehicle on my lane - grey land rover with no lights on.
He almost hit my back, but somehow managed to overtake me and then pulled in front of me, stopped blocking two lanes and come to my window shouting about stupid lorry drivers (he haven’t noticed yet, that I am polish). He was shouting and shouting, and he has so much to tell, so when he started to anticipate how it will be, when he will call police to report me, i interrupted him, gave him my mobile with 112 number choosen and told him “ok, call the police and tell them “lorry driver haven’t seen me, as I was driving with no lights on during heavy shower””. He then was speechess for few seconds and then he showed me his fist and told me “You polish drivers!!! You are the worst!!! I will show you all one day” then very calmly returned to his car and drove away.
I got great support from driver of some german lorry stopped on the right lane 
Heh, nice one Orys.
And why is it drivers of the most camoflaged cars never use lights? It’s white cars without lights in fog, and grey ones in the rain, why are they the most idiotic ones?
But, from the other side, plenty of british drivers use set parking lights + fog lights, to blind you up
orys:
I have in my car (british one) four opportunities: parking lights, which are turning to daylights, when I switch the ignnition on, then short beam and main beam.
- parking lights = side (marker) lights or running lights.
2) which are turning to daylights, when I switch the ignnition on = dim-dip? (A late 80s thing which the UK got a bollocking over by the EU)
- short beam = dipped headlights.
- main beam = main headlights.
I think I know what you mean Orys. Just clarify the 2nd one.
Sorry if I don’t used correct names for them. I just translated them straight from polish.
macplaxton:
- parking lights = side (marker) lights or running lights.
By that I mean just a small bulbs like these ones:
2) which are turning to daylights, when I switch the ignnition on = dim-dip? (A late 80s thing which the UK got a bollocking over by the EU)
They are called in polish “lights to drive during daylight”. Some vehicles have them integrated in headlights (like my old nissan) and you can also buy they separaterly if you want, as if you don’t have one of them, you must drive on dipped headlights. They are popular in scandinavian cars and often do not require rear lights to work with them at the same moment. It’s a bit bigger bulb in my car, but still nothing to do with main lights.
- short beam = dipped headlights.
- main beam = main headlights.
I translated them like that as in common polish we call them “krótkie” = short and “długie” - long, but official name for them are " swiatła mijania" = “passing lights” and “światła drogowe” - road lights.
So sorry for a mess, but some parts of english vocabulary are still a white areas for me 
Ironic that it takes a guy whose English isn’t 100% fluent to give these things their correct name… thank you Orys they are PARKING LIGHTS not “side-lights” and it’s high time their use on moving vehicles was outlawed.
As other posters have correctly said they are darned near invisible on modern cars and trucks, because instead of being a seperate lens as they were on a lot of older cars, they’re now a teensy little capless bulb stuck in a huge expanse of glass lens, and the pinprick of light which they do give off is diffused so much as to be useless.
My lights are either off completely or straight onto dipped headlights. Happens in the USA, Canada and a lot of other countries.
I fail to see a single reason why anyone should use “side-lights” only when driving.
Given that the Highway Code has recently had a major overhaul it’s farcical that this outdated and potentially dangerous piece of legislation stayed in.
gnasty gnome:
Ironic that it takes a guy whose English isn’t 100% fluent to give these things their correct name… thank you Orys they are PARKING LIGHTS not “side-lights”
That’s how they are called in polish and as far as I know in most other languages. Becouse they are to be used when car is parked only to mark it’s position on the shoulder
My lights are either off completely or straight onto dipped headlights. Happens in the USA, Canada and a lot of other countries.
I’m doing the same, unless I drive vehicle with day lights as mine and it’s not sunny or local law require me to do it.
And, I forgot, I use them also, when I am going FROM the west on sunset or FROM the east on sunrise, as that’ll help other drivers, blinded by low sun, to see me.
the talk on this post is about sidelights but there are two sorts - the little silly ones that are about as much use as a flashlight with a battery that is about to die - and dimdips
dimdips are great to use in well lit 30 zones and I have never had a problem with regard to safety when using them but it can be usefull to switch to normal dipped if approaching a blind type of jucntion where the light being thrown forward can give another vehicle prior warning to your approach.
Rog you beat me to it. Dim dips were great. Mostly to be found on late 80’s to early 90’s cars i think. My 93 Sierra has them & so does a friend’s 94 Rolls Royce.
Unfortunately the idea seems to have been dropped in more recent years.
Dim dip prevented you from being able to drive on parking lights as when the engine was runnibg and the parking lights turned on, the headlights automomatically illuminated at half voltage.
They were good for in town driving, particularly in the wet when dipped headlights can cause unwanted reflections off the wet road surface.
The Audi I used to have was fitted with ‘daytime running lights’. Many Audis have them. They were quite bright. Only fitted at the front.
madtrucker:
* use headlights at night, except on a road which has lit street lighting. These roads are generally restricted to a speed limit of 30 mph (48 km/h) unless otherwise specified
What if the road has streetlights but has a limit over 30mph? The way this reads suggests you wouldn’t need headlights on these roads as well 
Thanks for the explanation orys.
gnasty gnome:
…they are PARKING LIGHTS not “side-lights”
Parking lights are what you have on VWs and the like when you leave an indicator switch on and the ignition off. A white light to the front and a red to the rear, but only on one side of the car
Sidelights to me are when “your parking lights” are on both sides, I don’t advocate using them whilst moving, but I’ll still call them sidelights to differentiate from the above.
gnasty gnome:
I fail to see a single reason why anyone should use “side-lights” only when driving.
I’ll give one, when the dynamo (yes, I’m talking dynamo and not alternators) has packed up and I need to get across a built-up area with street lighting. Besides, nowt wrong with things as it is. Change would be one step closer to DRLs. I don’t want some nanny state insisting that all new cars and motorcycles have DRLs. (*DRLs = another EU crackpot idea)
Rog & Driveroneuk, I did mention those dim-dip things in passing and the reason you don’t often get them much anymore is HERE
macplaxton:
Sidelights to me are when “your parking lights” are on both sides, I don’t advocate using them whilst moving, but I’ll still call them sidelights to differentiate from the above.
In other languages these are just “one-side parking lights” and normal parking lights are just normal parking lights. Off course I will not teach you how to call you in english, but I am not suprised, that you must have everything made your own way