The main function of a car battery is to start your car. Today, most cars have a single maintenance-free 12-volt acid battery. The car battery is rechargeable. It uses its charge to power the vehicle systems while it’s parked and to turn over the engine when you want to start it.
Once you start the car, the alternator generates additional electric power to recharge the battery.
Over time, the battery loses its capacity or ability to hold charge. One day, a weak battery will not be able to start your car. Often, this happens when the weather gets hot. Most consumers believe the cold is the enemy of the battery but heat is the real enemy. More batteries fail in the heat than in the cold.
When the battery is too weak to turn over the engine, the car will need to be boosted to start the vehicle. To avoid this situation, the battery should be replaced before its capacity drops to a critical level.
On average, a car battery lasts from 3 to 4 years. The battery lasts longer if the vehicle is driven daily and the battery is kept fully charged. When the vehicle is parked for extended periods of time, the battery deteriorates sooner.
How can you tell that the battery capacity is getting low? Are there any signs that a car battery is failing? Yes. When the battery is weak, you might notice that the engine turns over slower than usual and the dash lights flicker or dim when you are starting your car.
We recommend you have your battery tested by a qualified technician at least once a year after it is 2 years old.
Can a problem with battery terminals cause the vehicle not to start? Yes.
If one of the battery terminals is loose or corroded see picture, it may cause many problems including a no-start.
Many reputable repair shops visually inspect the battery terminals during regular oil changes. Your mechanic may recommend servicing battery terminals if they are corroded.