With the Volkswagen Type 3, the factory had already noticed that unprotected generator connections could lead to unpleasant incidents, so protective rubber caps or boots were installed. It is rather strange that they only started using these caps on the VW Beetle and Karmann Ghia in 1971. This was not only to ensure that one could not accidentally connect the two poles, but also to protect against moisture.
The same rubber terminal boots were later applied to cars equipped with a seat belt warning system, to protect the switch that handles it.
On VW Type 3 models equipped with a fuel-injected engine, the same protective cap was used to protect the terminal of the oil pressure switch for idle advance.
Over time, these rubbers dry out and no longer offer the protection they are supposed to, and in many cases, they are not even there anymore.
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