The golden rule for the car owner is to check the serviceability of the systems regularly (at least once a year).
If the car is second-hand, the matter of periodic inspection is obvious.
As for the new modern machines, they have built-in electronics that control and monitor the system performance. However, sometimes it is impossible to identify the cause. Sometimes the sensors may fail.
Diagnostics is a way to check the technical condition of the car without disassembling it and to quickly fix the problems detected.
This procedure includes the following work:
Particular attention during diagnostics is paid to the control units. If you compare the car with the human body, the ECM is the "brain" of the car, this is where all the other systems are controlled. Inspection can quickly determine if all mechanisms are working, if signals from sensors are being received, and if voltage is present in all power circuits.