Car fuses

Automotive fuse - how it works and what is its function

Although car fuses are much smaller than fuses in a home electrical system, they operate on the same principle - they protect the car against serious breakdowns and properly selected, they determine the correct operation of electrical devices in the car installation. When one of them blows (when a short circuit or significant long-term overload in one of the circuits has occurred), the device protected by the fuse is turned off. The light in the cabin or the radio can be turned off, or even the engine shut down - usually due to a fault in the ignition system, injection system, or some other hardware or software malfunction. The automotive electrical system uses many fuses (even approx. 50), which is necessary due to the presence of a large number of electrical systems with different rated voltages - they are powered from separate circuits. Thanks to this, the failure of e.g. wipers does not stop the engine. Automotive fuses are used, among others to protect the circuits of horns, cabin lighting, alternator, fuel pump, air conditioning engine control unit and front and rear windows heating. Vehicle fuses blown and thus protect the car's electrical system against much more serious damage. When a short circuit or overload occurs, the respective fuses take the load, which then results in the disconnection of the relevant electrical circuit. Thus, the fuse blows. Thanks to this, the entire electrical system is not damaged, and even in extreme situations, it does not cause a fire.

Automotive fuse - typical values ​​for rated current and corresponding colours

The most important parameters of automotive fuses are rated current and rated voltage. Thus, we can distinguish the types of car fuses. Most often, the operating voltage of automotive fuses is 12V or 24V. In terms of rated current, there are more types of fuses, available for rated currents from 1A to even 60A. The colour of the housing indicates the rated current of a given fuse. The most common fuses in terms of colour and the corresponding rated current are:

grey - 2 A.

purple - 3 A.

orange - 5 A.

brown - 7.5 A.

red - 10 A and 50 A.

blue - 15 A.

yellow - 20 A.

white - 25 A.

green - 30 A.

orange - 40 A.

How to replace automotive fuses?

Before replacing blown car fuses, check that this is necessary. To do this, it is worth removing the fuse board cover and then, on the inside of the cover, locate the place where the potentially failed fuse is located. Then remove the fuse with a gripper. If it is burned out (no acoustic signal from the multimeter during the continuity test), replace it with the same, but the new one. So it is worth having in your home workshop a set of car fuses consisting of several fuses with different values ​​of the rated current. Place the new fuse in the right place, also using the gripper. Press the upper part with your finger and it's ready. It is not difficult to replace the fuses yourself, but you need to locate the blown place well and assess whether it is blown. Of course, it is also worth having a car fuse set and carrying it in the car, especially if we are going even on the shortest journey.