After a throttle damper has died in a W202 and there are some opinions that the voltage peaks when reconnecting the battery would be the reason for this, I am interested in the following: Are overvoltage protection devices used in cars? If yes – in what number – at which installation location or at which installation locations is a simple 12V/500A DC metal oxide varistor sufficient for discharge? For example Conrad there is an overvoltage protection for approx. 11€ with connection cables. A surge protection is usually effective when it is installed where voltage peaks arise or penetrate a grid. What sources of voltage peaks can be in the on-board electronics?