Is the Battery Bad, or Is It a Bad Alternator?

Bad battery? Bad alternator? Bad starter? Many times, when there is a problem with starting a vehicle, the battery is the first suspect. But, in some cases, the problem started earlier in a related component.

How can you know if it’s your battery or your alternator? See the diagram below.

Electrical flow

In the diagram above, the battery provides electricity to the starter to start the car. The alternator returns the energy that is removed for the starting of the car to the battery. If the battery cannot hold the electricity long enough, there will not be enough power to start your car. If the starter requires too much energy to start the car, the alternator may not have enough power to recharge the battery. If the alternator does not regulate the charge to the battery, the battery may get damaged.

All components must work together.

Bad alternator vs bad battery

If the components are not working properly in conjunction with one another, your vehicle experiences problems. But you are probably still wondering, “How do I know if it’s my battery or my alternator?”

Watch for the following signs that indicate a problem with one or the other component:

Bad alternator:

• Frequent engine stalls: If the engine stalls immediately after you jump-start the car, you probably have an alternator issue.
• Flickering or overly bright headlights: Uneven lights indicate inconsistent power from the alternator.
• Dim interior lights: Lights that dim gradually as the engine is running indicate a failing alternator.
• Squealing noises: Squealing that gets louder when you run the heater or sound system may indicate a bad alternator.
• A burning smell: The smell of burned wires may indicate your alternator has worn out.
• Malfunctioning electrical accessories: If the alternator is bad, you may experience problems with your stereo, power windows or speedometer.

Bad battery: 

• Warped battery: A distorted, warped or bloated battery is a bad battery.
• Rotten egg smell: This odor indicates the release of sulfuric acids due to a battery leak.
• Old battery: Batteries typically last three to five years.
• Corroded terminals: Corrosion will prevent the battery from being properly charged.
• Slow start/no start: If the battery is bad, the car will not have the power it needs to start.
• Dim dashboard lights/headlights: If the lights are dim or won’t turn on at all, you probably have a failing or dead battery.

Are you noticing any of these signs that you have a bad alternator or battery? Since some signs have overlap, it might be difficult to know if it’s your battery or your alternator, even when you see these red flags.

To determine which component is the culprit of your vehicle’s issues, it’s helpful to consult with a battery specialist. These experts can inspect and test the components and provide the appropriate repairs or replacement.

Get more answers

Texford Battery Co is your top source for battery info. We are more than a supplier. We are your industry experts, offering top products at the lowest cost and paving the way for new innovations in the battery distribution industry. Contact our team today to get the answers you need.

Categorised in: Battery Chargers, Battery Repair

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