When should you change a car battery?

As a general rule, car batteries need to be changed around 3-4years but keep in mind it’s an average. Before replacing the bosch batteries, it’s worth waiting until cannot be recharged. Note that the problem doesn’t only comes from the battery it-self but it could be link to some electrical issues. So when you see you need to have your car battery replace, ask your mechanic for a quick check of your electrics too.