Opening of the cover of the water tank can cause problems to the car engine and also to one who opened the lid
A very common occurrence when the car does not work is to see people opening the car engine water tank cover with the car still hot. This may bring two serious consequences one for the car and one for the person.
The person who does that is running a serious risk of severe burns with boiling water which can exhale system.
But the drive motor can heat up, because even if it has been removed all the circuit pressure, the air will enter the system and even that does not occur leaks, the result will be a car engine overheating because the air that entered the system causes blistering and impedes the circulation of water which cools the drive motor.