In which of these cases are you obliged to replace the tyre with a new one in a passenger car?

Visible deformations, cracks, or bulges on the side of a tyre indicate damage to its internal structure. This is a very dangerous fault, threatening a sudden tyre blowout while driving, which can lead to a loss of control over the vehicle. A tyre with such damage absolutely qualifies for immediate replacement, as its continued use poses a direct threat in road traffic.