Hello, I bought a Fiat Punto year of construction 2012 from a Fiat dealer. At the beginning there was no problem, the first 3-4 weeks the start-stop system worked quite well. But for some time the car stopped. To my driving profile: I drive daily about 15-20km in city traffic without traffic jams to work and also back 15-20km. Once a month there is also a pure highway track of about 600km. The car is perfectly maintained check booklet and there are no control lights. The day before I was at the dealer I drove also these 600km on the highway. This has read out the error codes (No available) and the battery tested (also without fault or fault). After the approximately 600km long highway ride the battery should have had a charge level of about 50%. The dealer said this is already correct, since the light engine does not charge the battery but only the battery needs to charge, which is also consumed. However, because the battery has such a low charge level, the voltage is too low to activate the start-stop function, the dealer has recommended to buy the battery for regular battery charging.