Media post: My car battery keeps going dead

If you have ever had a car with a battery that randomly goes dead, then you know what true frustration is. It can be one of the most annoying things to deal with because you never know when it can leave you stranded. And not only is that annoying, the problem can be difficult to fix too. The problem is sometimes the problem is a bad battery, sometimes it’s the charging system, and other times it’s a problem with the car’s wiring. It can be complex troubleshooting this sort of thing so, in most cases, you will want a professional mechanic to help you out. Just so you know, though, here are some of the things that can cause a battery to die on you.

A Faulty Charging System

The charging system in your car is designed to keep the car battery fully charged. If it malfunctions and provides a charge that’s too high or too low, then you can have a problem. Technically a fully charged battery produces 12.6VDC voltage. The service manager at Bosak Honda in Highland, IN, a premier Honda dealer, told us that to charge a car battery properly, the alternator must pump out some 13.5VDC or higher. If the alternator isn’t working properly then it likely is not charging the car battery properly. This can occur due to a loose connection, a bad circuit, or just a faulty alternator.

Short-Term Driving

Driving your car on short trips too often can contribute to a battery with a poor charge. This is because the most intensive use of the battery in your car is the initial engine starting phase (10-20 seconds) when a lot of amps are drawn. When short trips are the norm, though, you never give the alternator enough time to get fully charged. When in doubt, drive around for 10 mins or more just to keep a good charge in the battery.

Extreme Temperatures

Extreme cold and/or heat can stress the internal chemistry and structure of a car battery and induce premature failure and a weakened battery. In most cases, there isn’t much you can do about temperature extremes but it’s a factor that you should know about. Chemically what goes on is called “sulfation”. Sulfation is a build-up of lead sulfate crystals which can shorten the life of the battery and lengthen the amount of time needed to charge it. If your battery is heavily sulfated and you don’t drive your car a lot (as we discussed above) your battery may never get fully charged.

Excessive Current Draw

There are electronic devices in your car that will draw a small amount of power to stay on, things like your clock circuit and other items. Normally this sort of thing won’t kill your battery. However, if you have an excessive current draw due to a wiring short circuit or some other kind of fault, then your battery may lose its charge before you get a chance to drive your car again. Of course, leaving a light in your car on will do the same thing (as we all know!).