Skip the auto shop - Our mechanics make house calls

What Does the Alternator Warning Light (Battery Warning Light) Mean?

What Does the Alternator Warning Light (Battery Warning Light) Warning Light Mean? - main image

The alternator on your vehicle uses the rotational power of the engine to generate electricity and keep the car running. The alternator needs to maintain a certain voltage in order to keep the battery at sufficient charge while driving. As the alternator ages, it won’t be able to maintain a constant voltage and any fluctuations will be detected by the car’s computer.

What the alternator warning light means

When you start the engine, the car will check to make sure the alternator is outputting the correct voltage. This warning light will shut off after a few seconds if the computer has determined that the alternator is functional. When the light stays on, it indicates that the computer has detected an issue with the charging system.

If this light illuminates, try to use only necessary accessories like windshield wipers or headlights so as to avoid excessively draining out the battery. An alternator that is on its way out may cause this warning light to flash when there is a high demand on the battery. You can always save yourself a lot of trouble by paying attention to warning signs like this and trying to conserve your car’s battery.

What to do when the alternator warning light is on

As mentioned before, if this light is on, it means that your engine cannot produce enough power to keep itself running. Turning off all non essential accessories will help increase the distance you will be able to travel with a poorly charged battery. Keep in mind that issues with the battery can also cause the light to come on so if the battery is old, it should be tested as well.

It is better that you have a certified technician inspect and test your charging system to diagnose the problem in order to minimize any chance of permanent damage to your car.

Is it safe to drive with the alternator warning light on?

When this light is illuminated, your car is still somewhat safe to drive as you will have enough battery power to run the engine. However, it is still dangerous to continue driving for long distances or at high speeds as the battery will run out of juice and the car will be harder to stop without the assistance of the engine. If you are on the freeway and this light comes on, you should pull off the freeway and move to lower speed areas as soon as possible.

As always, our certified technicians are available to come to you to help you diagnose any issues with your car’s battery.

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

Rules of the Road For Iowa Drivers
Driving on the roads requires knowledge of the rules, many of which are based on common sense and courtesy. However, even though you know the rules in...
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....
P2422 OBD-II Trouble Code: Evaporative Emissions Control System (EVAP) Vent Valve Stuck Closed
Diagnostic Trouble Code (DTC): P2422 P2422 code definition Evaporative Emissions Control System (EVAP)...


Related questions

Q: Wrench light on dash after tune up and throttle body cleaning.

Hello there, many faults will cause the wrench light to be seen in your 2010 Ford F-150. When the throttle body was cleaned if too much cleaner gets on the throttle body sensor or into the throttle motor, then this...

Q: Car turns but doesn't crank

There are many things that can cause a no start condition. If your timing belt broke, for example the engine on your vehicle is an interference engine, meaning it hits itself internally when the timing belt breaks. This usually bends...

Q: Engine won't stay cranked over.

Check the engine oil level to see if there is oil in the engine. If there is oil in the engine and the oil light is on, then you will need to tap into an oil gallery on the engine...