Skip the auto shop - Our mechanics make house calls
  1. Home
  2. Articles
  3. Alternator or Car Battery: How to Tell Which Part Is the Problem

Alternator or Car Battery: How to Tell Which Part Is the Problem

alternator or battery

When you need to go somewhere and your car won’t start, it’s not unreasonable to think that you could have a car charging problem. A jump start might fix it in the short term and get you to work on time, or to your appointment, but ultimately, you’re going to have to find the origin of the problem and have it corrected. The problem could be in the battery, or the alternator, or even somewhere else in the car electrical system.

You can check out a few things yourself before you get in touch with a mechanic.

  • First, take a look at the battery. Start with this because battery problems are very common, especially in cold weather.

  • Look at the dashboard battery gauge to make sure that the car is still getting a charge even when it’s switched off. If the light is dim and flickering, then likely there’s a problem with the car battery.

  • Turn off everything, and check your battery connections for corrosion. Sometimes the problem is simply that there’s not enough contact.

  • If it looks like corrosion is the problem, you can remove the battery cables and use a bit of steel wool to clean up the corrosion.

  • If a cleanup solves the problem, great, but if it doesn’t, you may have a dead battery, or a bad alternator.

  • You can check the alternator by simply starting your car and then disconnecting the negative battery cable. Be careful doing this, though, because there are a lot of moving parts in your engine compartment that could cause injury. If the car stops when the battery cable is disconnected, the alternator is the likely culprit.

If the alternator is faulty, you’ll need to contact YourMechanic. Sometimes alternators can be rebuilt, but more often, they need to be replaced. YourMechanic can also test your battery to find out if it’s the reason why your car won’t start.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
Icon-warranty_badge-02

Skip the repair shop, our top-rated mechanics come to you.

At your home or office

Choose from 600+ repair, maintenance & diagnostic services. Our top-rated mechanics bring all parts & tools to your location.

Fair & transparent pricing

See labor & parts costs upfront, so you can book with confidence.

12-month, 12,000-mile warranty

Our services are backed by a 12-month, 12,000-mile warranty for your peace of mind.

Get A Quote

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.

GET A QUOTE

More related articles

How to Transfer a Car Title in Idaho
In order to prove ownership of a car, you must have the title. However, when a car is sold, given away or inherited, the title needs...
The Traveler’s Guide to Driving in Malaysia
CraigBurrows / Shutterstock.com Malaysia is a popular destination for many tourists today. The country has amazing sights and attractions that you will want to explore....
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...

Related questions

Q: Car was struck by lightning and won't start

Hello, thank you for writing in. Unfortunately, there is not a cut and dry answer for your problem. Lightning strikes are not created equal, nor is the damage they cause. You most likely have electrical issues, rather than something mechanically...

Q: Electrical signal to the injectors randomly malfunction

Hello. The issue you are experiencing is likely an intermittent crank position sensor failure. The crank position sensor is largely responsible for the fuel injector pulse because the pulse is alternated when the sensor passes certain points on the crank. If...

Q: Changed alternator now car seems to be in creeper mode.

Hi there. If the engine is not accelerating after replacing the alternator, then check the alternator and see if its charging the battery. Look at the cables and make sure that they are hooked up correctly. If the alternator is...