Each part of your vehicle has different characteristics that can make driving easier. But, it must be recognized, even if we spend a lot of time there, we do not always know the exact use of each element of our vehicle. Take for example, do you know what the function of those black lines on the rear window of your car is? Some would say that they only serve to beautify this area of the body. But it’s nothing. These horizontal bands have a very practical and even very useful advantage during your trip. We explain to you.
What are these horizontal black bands on the rear window of the car for?

Rear window of the car – Source: spm
Today, modern cars are equipped with multiple advanced electronic systems, such as cameras or parking sensors. However, the rear window is still just as important. and many drivers rely more on it than on these new technologies. However, in winter, visibility is not always optimal due to fog or frost. Remember that this is one of the parts most subject to this type of inconvenience: when the outside temperature is colder than the passenger compartment and there is a lot of humidity in the air, The rear window always ends up fogging up.
This is where these famous black bands come in, which are nothing more than electrical cables that act as small resistors. This current, when it begins to flow through the wires, by activating a specific digital switch, it generates heat and therefore increases the temperature of the glass. Thereafter, the glass begins to thaw, as warmer air contains more waterthus absorbing condensation.
In the first place, it consists of a tempered glass plate on which electrical resistances are added, powered by the car’s own electrical system, to allow the demisting and defrosting of the glass. Thus, thanks to the diffusion of hot air from the heating system, is it possible to defrost the rear window. Cold air, after heating, is pushed against the windows by fans. It is often dehumidified first, thanks to the air conditioning system. Also, after dehumidifying, the windows defrost more quickly (since water vapor is absorbed by dry air).
Please note that the heating effect varies depending on the power delivered by each heated surface unit. It is true that it can happen that the heated rear window is faulty and that the defrost function is no longer as efficient. This does not necessarily mean that the glass must necessarily be changed. Often, it is enough to carry out a repair with a professional for the problem to be solved.
Be careful not to damage these electrical wires!

Car window – Source: spm
To activate or deactivate the rear window de-icing system, you have to press one of the buttons available on the dashboard (the icon represents arrows attached to a rectangular panel). Once the power button is activated, the glass will revert to transparent after a few minutes, providing better visibility for the driver. This is the most appropriate way. Because, unlike the front windshield and the windows on the driver and passenger side, it is not affected by the air vents that, by projecting cold or hot air, they also have the function of opening the windows.
As explained above, the lead wires, which are wound along the length of the rear window, allow efficient flow of electrical current. Thanks to the heat it emits, this resistance will evacuate fog and frost very quickly. But this system is still very delicate and can therefore be damaged very easily.. Furthermore, to the extent that these electrical cables are fragile, therefore, it is necessary to be very careful during cleaning and maintenance operations so as not to harm them. Also, if your vehicle does not have these electric heaters, the only way to clear the fogged rear window is to use a chamois. A passenger in the back could do it for so you can have a better view.
Also read: This is what the horizontal lines on the rear window of the car are for.