While your car's battery provides the electricity necessary to start the engine, the charging system keeps the engine and electrical components like lights running smoothly. If the charging system fails or provides insufficient electricity to the battery to keep it topped off, your car may eventually stop. So, if the battery. Some issues that can cause the battery light to flash intermittently may be easier to resolve than others. Let's examine the most common culprits behind a battery light flashing on and off. One telltale sign that something is wrong with the alternator's electrical output is when the battery light comes on when accelerating. When increasing speed, your engine works harder and. While we listed some common reasons behind the dreadful battery light on your dash, your car may experience multiple issues simultaneously, like a failing battery, a bad alternator,. Several issues can cause your battery light to come on when your engine is at idle. But the first thing you should consider is your battery health. If you have an old car battery, it may not.