A flashing light on the mirror. An important signal for drivers

Drivers of vehicles equipped with advanced safety systems are usually well versed in how these technologies work and what their applications are. Nevertheless, other road users may not always know how to react to the presence of such vehicles. An example could be a situation where a flashing light appears on a car's side mirror.

Imagine that you're driving behind another vehicle or, moving on the left lane of the highway, you are starting to overtake the driver moving in the right lane. At such a moment, you might notice a flashing orange or red light on the left mirror of that driver. Sometimes this light is located near the mirror. This is a warning signal for you, as another driver, that you are approaching this vehicle. At the same time, it is a warning to you that the driver of this car is not able to notice your vehicle.

Such action is characteristic of the BLIS system (Blind Spot Information System), which is designed to warn the driver of the presence of another vehicle in their blind spot. The blind spot is an area that the driver is unable to see, even when looking in the side mirrors or turning their head.

In practice, the BLIS system monitors a much larger area than just the blind spot. It is designed to alert the driver about vehicles that may soon be in this blind spot. It can be assumed that this is the area from the center pillar (pillar B) to several, or even dozens of yards behind the vehicle next to it. However, it is important to note that the BLIS system does not warn about vehicles on the same lane, that is, approaching from behind the car.

The main goal of the BLIS system is to prevent collisions that could occur when a driver with the system decides to change lanes. The signal issued by the system is quite clear and unambiguous, but that doesn't mean the driver won't decide on such a maneuver. Therefore, seeing a blinking light in the mirror of another vehicle, you should be aware that it is also a warning for you: the driver of this car is not able to notice your vehicle.

Pay attention to the turn signals, which are mounted on the side mirrors in many cars and, from the perspective of a driver following from behind, may look similar to a BLIS system light. This is especially true in cars like the Seat Leon, where these two elements are very similar. So if you notice the driver of such a vehicle turning on their left turn signal and intending to switch lanes while you're driving next to them, you need to be aware that they probably cannot see your vehicle. They might also be waiting for you to pass or let them into your lane.