All modern vehicles today have a 12-volt battery, which is also rechargeable. This battery provides power to practically all electrical components of the vehicle, such as its ignition system, engine control unit, headlights, radio, interior lights, etc.
If the battery does not recharge or discharges completely, then your vehicle will not be able to function.
In the past, car owners had only two ways to know when their batteries were about to die: either to test the battery voltage or to wait until their headlights began to flicker.
Nowadays, in modern vehicles, the dashboard contains a battery warning light that lights up whenever the computer detects a charging problem. This is useful because it gives you the chance to address the issue before the battery is completely drained of stored energy. This way, you won’t be stranded with a dead car.
What does it mean when the battery warning light comes on?
There are various issues that can trigger the battery warning light on the dashboard. Below, we will present the top 7 defects to help you diagnose the problem.
Once you’ve identified the cause (or causes), you can work to correct the issue. This may involve fixing certain components or replacing entire components or parts.
Battery Terminal Corrosion
This is a common issue that can cause the car’s engine to not start due to the starter motor turning slowly. Corrosion on the battery terminals can interrupt the flow of electrical energy and prevent the alternator from doing its job.
When the battery terminals are corroded, the battery warning light on the dashboard will be constantly lit. Remedying this problem is relatively easy. Simply disconnect the battery cables and then use a mixture of baking soda and water, along with a toothbrush, to clean the battery terminals.
Weak Battery Cables
Similar to corroded terminals, a weak battery cable that is not tightly secured can trigger the battery warning light. This often happens after replacing the battery or hitting a pothole very hard. To address the issue, ensure that the cable is as far down on the battery terminal as possible and tightly secured. If it’s not, use a wrench (typically a 10mm wrench) to tighten the battery cables.
Old Battery
If your vehicle’s battery is over 3 years old, it may be nearing the end of its life, especially if you drive the vehicle daily and in hot weather. Unfortunately, excessive heat significantly reduces battery life. Even though car batteries are sold with warranties of 48, 72, or even 96 months, don’t expect them to last that long.
Depending on the battery’s failure during the warranty period, you may receive a new battery. To check if a battery is defective, use a multimeter to test its voltage. Connect the negative cable to the battery’s negative terminal and the positive cable (red) to the battery’s positive terminal.
You should have a voltage reading somewhere between 12.4 and 12.7 volts. If the result is below 12.2 volts, the battery needs to be replaced.
Faulty Alternator
Alternators typically last around 5 to 7 years. As you know, the alternator is responsible for keeping the battery fully charged as you drive the vehicle. However, if you have a faulty alternator, it won’t be able to maintain the battery’s charge.
This will cause the battery warning light to come on after there’s an inconsistency in charging. Once the alternator “dies,” the remaining energy in the battery will be depleted within a few minutes. If you have a faulty alternator, you’ll need to replace or repair it.
Damaged Alternator Belt
The alternator belt connects the crankshaft to the alternator. If you have a damaged, weakened, or broken belt, your alternator won’t function properly. Consequently, your car’s battery won’t receive the necessary charge to power the vehicle’s electrical components. So, the battery warning light will come on as a result. Replacing the alternator belt with a new one is the only option.
Battery Ground Cable
Your vehicle’s ground cable connects to the car battery’s negative terminal. If the negative battery cable ever becomes excessively damaged or worn, it will affect the flow of energy to your vehicle’s electrical components. Additionally, a faulty ground cable can cause the battery warning light to come on while you’re driving. If you see any damage to the ground cable, you’ll need to replace it.
Too Many Accessories Running
If the battery has the correct voltage, and the alternator is recharging it as it should, running numerous electrical components while driving shouldn’t trigger the battery warning light. However, if the charging system isn’t operating optimally, using many electrical components simultaneously during driving can quickly discharge the battery.
Heating, air conditioning, power steering, and your car’s headlights all require a lot of energy. Once you start adding other accessories like windshield wipers, rear window defroster, fuel pump, GPS system, DVD player, or even charging your mobile phone, the electrical demands begin to add up.
If you notice the battery warning light coming on while you’re driving, try turning off the A/C or any other non-essential components to see if that helps. At the very least, you’ll conserve the amount of energy stored in the battery to allow you to reach your destination and then address the problem.
Image Source: cartreatments.com, action4energy.org, time.com