1. Human Error:
you've probably done this at least once in your life you come home from work, tired and not really thinking, and left the headlights on, didn't completely close the trunk, or even forgot about some internal lights. Overnight the battery drains, and in the morning your car won't start. Many new cars alert you if you've left your lights on, but may not have alerts for other components.
2. A Defective Alternator:
Another cause of battery failure is actually not related to the battery at all - but to the alternator. When the car is working properly, the alternator is what supplies electrical power to primary systems, by converting some engine power into electricity. This power is also used to recharge the 12v battery, ensuring that it has enough power to start the car. If your alternator fails to charge your car battery, it will drain over and over again as you start your car - and eventually fail, requiring you to jumpstart your vehicle. If your battery keeps dying, and you're noticing other electrical issues like flickering lights or strange, abnormal noises, you may want to get your alternator inspected by a professional service like Ride Time.
3. Parasitic Drain:
Parasitic drain is due to components in your vehicle continuing to run after the key is turned off. Some parasitic drain is normal - your battery delivers enough energy to keep things, like your clock, radio presents, and security alarm operational at all times. However, if there's an electrical problem - such as faulty wiring, poor installation, and defective fuses - parasitic drain can exceed what's normal and deplete the battery.
4. Old, Worn-Out Battery:
Batteries don't last forever - in fact, most car batteries only last about 5 years. If you have an old car battery, it may just be on its last legs, and unable to deliver the power required to start your car engine. Over prolonged, regular use, your battery goes through quite a bit of abuse. Plate corrosion, loss of water, and the buckling of lead-acid plates are all common, and can have a negative impact on the ability of the battery to hold a charge. So if you're driving a car with an old battery, chances are that you'll just have to replace it. But the good news is that it's easy to make sure this is the problem - just remove the battery and take it to an auto parts store, and they'll be able to test it for you.
5. Extreme Temperature:
Whether extremely hot (over 100 degrees Fahrenheit) or cold (under 10 degrees Fahrenheit), temperatures can cause lead sulfate crystals to build-up. If the car is left in such conditions for too long, the sulfate build-up can damage long-term battery life. It may also take a long time for your battery to charge in these environments, especially if you only drive short distances.