Strangely enough, one of the common causes of the engine overheating at Hyundai Sonata NF becomes a battery. You can check this by turning the ignition off and off again. If the arrow points to the fact that the temperature is normal, then the problem is really in the so-called masse shortage.
In order to solve this problem, the first thing to do is check the battery terminals-they must not be oxidiated or unreasonably prolonged. If the battery check and prevention did not help, an additional mass wire is required. A wire is already fitted to the vehicle connecting the body and the engine. It is located between the arm arm (over the generator) or the intake manifold and the front board of the cab, however, in the temperature sensor assembly and temperature indicator on the instrument panel, there are design deficiencies leading to the malfunction of the indicator and requiring the installation of an additional wire.
The copper "perm" may be used as a wire from the VAZ.
It is possible to connect the wire either in parallel with the normal mass (there are additional threaded holes both on the manifold and on the board of the cab), or between the minutes of the battery and the safety of the fuse assembly.