Five Things That Drain Your Car Battery

Five Things That Drain Your Car Battery

Nothing is worse than returning to your parked car only to discover its battery is flat due to parasitic draws. 

When you turn off your vehicle’s ignition, there are still several electrical operations the car is running in the background, which can drain a car battery. 

These parasitic draws are typically out of sight and difficult to detect. One common example of a significant parasitic draw that most of us have experienced is leaving the headlights on when the car is parked. Here are some of the things that drain your car battery:

1. You Left The Headlights On

If you suspect you left the headlights on and can prove this drained the battery, you’ve found what has drained your battery. 

Even when you’re sure it’s not your headlights, it is the best first check to conduct as a car owner.  

Simply test whether your car’s headlights are turning off properly. In most modern vehicles with LED headlights, it will take longer to drain a battery. Also, vehicles with LED lights will have an automatic off switch. 

But for older vehicles with halogen lights, you’d be surprised how quickly it will drain a car’s battery. 

A simple solution is to check if you can change the light bulbs for more energy-efficient ones if the issue is simply leaving them on. Another action plan is to check if the switch is working correctly; if not, an auto-electrician can assist.  

Again, it’s in your best interest to take it to a professional for more complex issues. 

2. Something Else is Causing a Parasitic Draw

Modern cars have a million and one features built into them that rely on being powered by your vehicle’s battery. 

It could be your radio, electric windows, heating and cooling, seats, interior lighting – the list goes on.

If you are waiting in a car park with all these gadgets running, without the engine turning over, you can drain your battery very quickly. especially with air conditioning and the radio running at the same time. 

If you plan on using all these features while waiting, leave the engine idling to ensure it charges the battery. When your car’s engine is running, it will use the alternator to keep the battery charged. 

Another factor is if one of these electric features won’t turn off when the car’s ignition is off. This will drain the battery. 

For example, if your vehicle’s window motor is running, or jammed on, even when the car is off, it will drain the battery. 

Finding the source of a parasitic draw can be reasonably easy to locate, but it will require an expert to assess what is wrong and, in most cases, will require replacing said problem part. 

3. Bad Battery Connections

Battery maintenance is an area many neglect. But when your battery’s positive and negative terminals are in a bad state, you can be sure it will cause a problem. 

Over time, terminals can become corroded, and when they do, they will experience issues with start-ups because the electric charge can’t move from the battery to the starter motor. 

A bad connection could also be due to a loose fit because your bolts have not been tightened. To check if this is the issue, look at your batteries’ terminal points. A simple scrub with bicarbonate of soda and warm water to remove grime will help if they look dirty. 

If this doesn’t work, it might be a more complicated issue. 

4. Bad Alternator

When your car is moving, it draws its power from the alternator. Your car’s battery is only used to turn over the starter motor, requiring a large jolt of amps. 

If your vehicle’s alternator isn’t working, your car’s power will be drawn from your battery. Even over a single journey, a bad alternator will result in the vehicle losing all power. 

A bad alternator will be a prominent issue, as it usually results in the car powering down while moving, resulting in the failure of power steering and other features. Some modern cars have fail-safes for this. 

But, if your alternator is simply faulty, and not providing enough of a charge, your car could be running down your battery until it is flat. 

This will require an auto-electrician to replace or repair the alternator.  

5. Extreme Temperatures

In certain parts of the world, extreme temperatures, from heat or frost, will affect your battery’s ability to perform and, over time, lose charge. 

Also, with extreme temperatures, a vehicle’s ability to recharge is hampered, especially if you are prone to short drives. 

If none of these issues seems to be the cause of your car’s battery draining, it might be time to take it to an auto electrician. 

Or it could just be an old battery that simply needs to be replaced. 

Get Your Battery Replaced With a SABAT

It’s never been easier to replace your car’s battery with SABAT Xpress outlets nationwide and SABAT battery stockists.  


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