You’ve probably been there. You’re in hurry, you jump in your car, you turn the key and nothing happens. No starter noise, no lights, no nothing –drat, your battery is dead. It’s not much fun but it’s a rite-of-passage for most car owners. It seems to happen to everyone at some point in their automotive driving life. Unfortunately, finding out why this happened isn’t always so straight forward. We asked Reedman-Toll of Langhorne, a local Chrysler, Dodge, Jeep, Ram dealer in Langhorne, PA, what they thought and they suggested 4 things.
Human error is probably the number one reason that batteries go dead overnight. It happens to everyone. You come home from work, plenty tired and you accidently leave the headlights on, or the truck open, or the map light on. The result is a flat dead battery the next day. What a bummer. Fortunately many new cars warn you if you’ve left your lights on, but usually don’t have alerts for other components.
All vehicles have a little parasitic power drain. This is a tiny amount of power that is needed to power your clock, radio presets, security alarm, etc. The manufacturers of these devices design them so there parasitic power drain is very small. These devices shouldn’t be a problem. Problems occur when there is an electrical problem. This can be any number of things. A short circuit because a wire over heated, a mouse nibbled on a wire under the hood, a wire’s insulation melted off, or many other things. This sort of drain can be measured and a professional mechanic will be able to fix it.
If your charging system isn’t working properly, your car battery can drain even while you’re driving. The alternator in your car is designed to charge your battery but it may not be working properly. Sometimes alternators work less than 100%. In fact, this is not uncommon on an older car. Diagnosing this isn’t difficult. It just requires measuring the voltage across the battery while the engine is running. (It should read approximately 14 volts.) If you have an underperforming alternator, the best solution is to replace it with a new or rebuilt one.
If your battery is old, it might not hold a full charge. Batteries generally last 4 to 5 years so if your battery is that old and you find it going dead often, you likely need to replace it. The general symptom is either a dead battery but more often it is one with a low charge. When you turn the key, the engine cranks slowly and then stops. This is especially common during cold weather when a car engine needs lots of power to turn over.
Having a battery that won’t hold a charge is frustrating, and figuring out what’s causing the problem can be tricky. Assuming that the cause of the battery drain is not human error, you probably want to have a professional mechanic look at it so it gets taken care of quickly.