Common signs
- The engine turns over slowly when you start it, especially in the morning or in cold weather.
- Headlights and dashboard lights look dim, or they flicker when you try to start.
- You hear only a click, or nothing at all, when you turn the key.
- The battery case looks swollen, there is white or green powder around the terminals, or there is a smell like rotten eggs.
It may not be the battery
A loose or corroded terminal, a faulty alternator that does not charge the battery while you drive, or something left switched on can all drain a battery. If you replace the battery and the same thing happens again soon, ask the mechanic to test the alternator and look for something draining power overnight.
What to do, and what to avoid
- Get the battery tested before it fails, especially before summer or winter and if it is several years old. Testing is quick.
- If the car won't start, do not keep cranking it for a long time. Wait a minute between tries.
- Jump-starting with a wrong connection can damage the car's electronics or make the battery spark. Ask a mechanic or someone who knows how to do it, and follow the car's manual.
- Don't smoke or hold a flame near a battery, and don't open a sealed battery.