Last Updated on February 27, 2023 by Kevin Chen
Image source HERI
A battery is responsible for cranking your car. You will always freak out when the warning battery light on the dashboard turns red. It means that your battery needs urgent attention unless you are ready for a serious let down. However, the battery light warning could also mean that there are other electrical faults in the vehicle that need to be attended to. Maybe the alternator is damaged or any other serious fault.
While it is easy to replace a bad battery, a bad alternator is likely to give you serious troubles. In this article, we are gong to discuss issues surrounding bad battery vs bad alternator.
What role does a car battery play?
The primary function of a car battery is to provide power needed to start the vehicle. Other than that, it also provides electric energy needed to keep the electric components of the vehicle running when the alternator is not running. These components include the car alarm among others. It serves as a reservoir of the electrical energy needed to start the engine while at the same time run the necessary accessories.
The battery also serves as a stabilizer of the electric supply and distribution system in the vehicle. It takes care of the constant fluctuation current of the power generated by the vehicle and ensures that constant power is supplied to the essential components. Keep in mind that the fluctuations can easily damage these components, especially when the current tends to fluctuate to a higher scale.
What is the function of an alternator?
There is a close relationship between the battery and alternator. The main function of an alternator is to generate the electrical power that will be used to charge the battery and at the same time power various electrical components of the vehicle when it is running.
A car’s alternator works by converting the electrical energy from one form to a more relevant-mechanical to electrical. This electrical energy will then be used by key components of the car. Some of the energy will be channeled to the battery to replenish or recharge it.
How does an alternator work?
This device comprises of a magnets and coils which when combined create an electromagnetic field. On the other hand, the constant rotation of the engine’s crankshaft spins the rotor in the alternator. This ends up creating alternating current (AC) which will be converted to a more usable DC current by the rectifier.
When the alternator is running, the car will not depend on power from the battery. As we have mentioned, some power from the alternator will be used to charge the battery.
Keep in mind that alternators are also stabilize the voltage supplied to the electrical components of the vehicle.
Signs of a bad battery
A bad battery is likely to lead to a myriad of problems in your car. It is important to be fully ware of the signs and take action in time before the issue becomes something big that will be difficult to handle. Here are the most common signs of a battery.
Engine won’t start or cranks slowly
The primary function of the battery is to crank the engine. So, if the engine does nor start when you switch the ignition could mean that either the battery is weak or completely dead. For a weak battery, the engine will crank slowly and you will feel it struggling to start. For a dead battery, the engine wont start at all.
Let’s say the engine is not running, meaning that the battery is the primary source of power at that point. Turn on the car but do not crank the engine. Are the lights dimmer than they usually are? This could be a clear sign of a bad battery, or it is weak hence incapable of supplying adequate power to the key components. You can also test with the car audio system. If it shows any sign of underperformance, it could be a sign of a bad battery.
Warning light on dashboard
The good thing about modern cars is they will always communicate with you in case of a problem. A battery warning light on the dashboard is a sign of a bad battery. Whether the issue is major or minor, you will still need to attend to it. Maybe the terminals are not well attached properly or the battery is not fully charged. Constant malfunction of other electric components can also be a sign of a bad battery.
Corroded terminals and bulging battery casing
Image of corroded battery source NAPA
The physical deformities can also point out to a bad battery. Corroded terminals can easily impair the flow of current to the target electrical components of a vehicle. This corrosion may also hinder proper attachment at the terminals.
Also, if you notice that your battery is bulging or swollen chances are it is damaged. Leakage of fluids from the battery is another possible sign of damage.
Sometimes you don’t have to do much to know that your battery is bad. You only need to trace the date that you bought it and know how long it has lasted. Car batteries have lifespans and they tend to be problematic once their charge cycles end.
Signs of bad alternator
Since an alternator is part of a vehicle’s electric system, it tends to have similar symptoms to that of a bad battery. Here are some of the signs of a bad alternator.
The battery could be dead because it has not been charged, a task that should have been done by an alternator. Also, slow cranking means that the battery has no power due to low charge or has not been charged at all. The current capacity of the battery is too low to crank the engine.
So, before you blame the battery for your vehicle not cranking, the problem could be with the alternator.
Smell of burning rubber or wires
If the smell of a burning rubber or wire hits you whenever the engine is running, this could be an indication of a damaged alternator. Probably some parts of the alternator are wearing out and need to be replaced.
The belt drive of an alternator is always under stress and friction which generates significant amount of heat hence the burning rubber smell. An overworked alternator may also end up burning some wires hence the odor. Similarly, damaged wires in the alternator can increase resistance to the flow of current hence the heat that will eventually cause the burning smell.
The strange noise emanating under the hood could be an indication of a damaged alternator. While it is easy to ignore some noise, you should get concerned if it persists.
The whining and growling noise from the alternator could be due to the worn-out bearings or misaligned pulley rubbing itself against the sides of the alternator.
Trouble staring the vehicle and frequent stalling
While this a battery-related problem, a bad alternator can also lead to a hard start. This happens when you hear clinking sound whenever you turn the ignition on.
Also, frequent stalling of the vehicle whenever you are driving can also be another sign of a bad alternator. Chances are the spark plugs are not getting adequate power from the alternator to keep the vehicle running, a factor that leads to frequent stalls.
Underperformance by the electronic components and accessories
You are likely to see these problems after cranking the engine or when it is already running. They include dim lights, underperforming audio systems, among other accessories. The windows and mirrors may fail to respond when the vehicle is running. Chances are the alternator is not supplying adequate power required to run these components.
Any of the above symptoms raises red flags about the alternator and you need to give it full attention.
What causes bad battery and bad alternator?
The most common causes of bad battery include:
- Age; that is when the battery has been used for more than 3 years
- Using the battery under extreme temperatures
- Corrosion on the battery terminals leading to loose terminals and current leakage
- Constant overcharging of the battery, a factor that kills the cells hence cutting down their lifespan.
- Extended period of not using the battery leading to energy discharge
Causes of a bad alternator
The most common causes of bad alternator include:
- Age: when the alternator has been in used for more than 7 years
- Electrical overload meaning that there are many electrical components in a vehicle that strain the alternator
- Faulty alternator belt
- Faulty voltage regulator, a device that controls the amount of power an alternator generates.
How to fix a bad battery and alternator
How do I solve the problem or a bad battery or bad alternator? The surest way is to identify the root cause of the problem. As we have seen, the two car components tend to have the same symptoms. So, you should establish whether the problem is on the battery or alternator. From there, you can find the possible cause and solutions.
If one of the solutions is to replace, ensure that you buy high quality battery or alternator that will work perfectly in the vehicle. In all these steps, seek help from a professional mechanic.
If you want to find more Electronic Components Distributors, please check out the following articles:
- Everything You Need to Know About 555 Timer IC - December 4, 2023
- The Role of Electronic Distributors in the Evolution of Electric Vehicles - December 4, 2023
- IC Chips in IoT: Powering the Internet of Things Revolution - December 4, 2023