When Your Battery Fails Too Often, Something May Be Happening Overnight
If you've just returned from your auto-parts supplier with another brand-new battery, you may think that this is an all too regular occurrence. After all, if you've had to call in your battery warranty on too many occasions, you may be thinking that your car is the problem rather than the device itself. But what could be going wrong in this situation, and how can you fix it so you don't have to be on first-name terms with the store assistant any longer?
When more than one battery has failed before its time, it's likely that your car is requiring too much of the part. Certainly, the battery is designed to provide a big boost of power whenever you turn the ignition key, so you can click the starter motor into action and get on your way. It's also designed to deliver a "trickle" of power to a multitude of onboard ancillaries when the vehicle is not in motion. Indeed, the problem may lie in this latter area, in a phenomenon known as the "parasitic" drain.
In the Background
Certain components may still be active when your vehicle is parked up overnight. These may include a central computer, the cabin lighting system, an alarm, and various other electronic components, but the amount of power they use is very small.
Still, it's possible that a component is harvesting power from the battery when it should not be and is wearing the battery down during those long periods when you're not in the vehicle. This is also known as a "vampire" drain in the industry, and it can certainly cause excess wear and tear. If you only use a vehicle for short trips on a given day, then the battery may not have time to recharge itself fully, and, in short, it'll need to do far more work than it should.
Fixing the Issue
It may certainly be possible to check for parasitic drain by using a multimeter, but this is a fiddly job and is not easy for someone who is not mechanically inclined. In this situation, it may be better for you to take the vehicle to a mechanic who will perform a full electrical service and test each circuit to see what is happening. If they discover a parasitic drain, they can take care of that so your battery should last much longer in the future.
Contact a local car battery provider for more info.