Hello, have “new” bought a Polo 6N2 and unfortunately had to find out that I have a problem with the power supply. Although the battery is not yet a year old according to the previous owner, I have stayed down. Starting aid was enough that the car ran again. In addition, I charged the battery with the charger. Apparently, the charging was not enough. The next breakdown came. Also the purchase of a new battery did not bring any improvement. This caused suspicion of the alternator. Allerd The voltage was not sufficient when the engine was running. So the alternator definitely no longer charges. However, the old battery had to contend with lack of acid, which was more likely to close to overload. Does anyone have tips? Can it be a cable error (e.g. with the excitation)? Can the voltage regulator be replaced separately from the alternator? How do I check whether the alternator or Regle r are defective? Tips on cost savings are especially desired, because the car is the first for my son who is still an apprentice. Greetings and a happy new year wishes Thomas