To ensure the safety of all road users, certain rules and measures must be established. One of them provides for the use of automatic radars. Implemented since 2003 and placed everywhere in France, these devices are supposed to deter the most hurried motorists. Also, and in case you have always wondered if these work at night, here is the answer!
To reduce the number of fatal accidents on the roads, automatic speed cameras have been installed and here you will find everything you need to know about how they work.
Do the radars work at night?
As a motorist, you must ensure above all for your safety, that of the passengers who accompany you, without forgetting the rest of the road users. For this, the rule is simple: respect the highway code but, unfortunately, sometimes that is not enough. In fact, you are not immune to the arrogance of certain drivers, who do not hesitate to push the limits, exceeding the limited and authorized speed on various roads. To prevent this type of behavior and dissuade the most refractory, the managers of the national road network have installed automatic radars on the sides of the road. Its objective ? Flash and take a photo of speeding vehicles. If they are functional and operational during the day, some motorists wonder if these devices also work at night.

Speed camera on the side of the road – Source: spm
Automatic radar: day and night operation
When a motorist receives a particular speeding light flasher, the radar is responsible for automatically transmitting the information to the National Processing Center (CNT) for traffic violations whose purpose is to identify the owner of the vehicle based on the information collected.
After an officer or a judicial police officer has observed the violation, the violation report is drawn up and sent to the owner of the vehicle in question, who can choose to resolve or contest the violation. The notice received includes, therefore, the geographical coordinates of the place of the infraction, the time, the municipality, the axis as well as the direction of movement of the vehicle.. Indeed, and according to the site road safety.gouv.fr, radars work day and night and whatever the weather conditions.
Do all speed cameras flash?
All automatic radars are equipped with a flash that can be used depending on the light conditions and the model in question.

Vehicle flashed by a radar – Source: spm
- Turret radars: During the day, this security system does not fire a flash when all light conditions are met. However, an infrared flash visible to the naked eye can be fired when the latter are not favorable.
- Fixed speed cameras: if they are 1time2the3the generation or bidirectional, these radars emit a flash that is always visible when the violation is observed.
- Discriminant radars: these fire a visible flash when the violation is committed, especially if the vehicle is near the speed camera at the time of the violation.
- Radar section: fire a visible flash if not equipped with an infrared filter. The latter being, however, mandatory, take a photograph of the vehicles that circulate through the entry and exit terminals..
As you can see, the auto speed camera works day and night and in all weathers. So if you were thinking about avoiding a ticket for driving at night, you’ll think twice before breaking the highway code.
read also Why do radars never show the real speed of the car?