How to tell if a Subaru alternator is bad?
The alternator is a critical component of your Subaru's electrical system, responsible for keeping the battery charged and powering various electrical components while the engine is running. A failing alternator can lead to a host of problems, from dim headlights to a completely dead vehicle. In this article, we’ll explore the common signs of a bad alternator and what you can do to address the issue.
Signs of a Failing Alternator
Recognizing the symptoms of a bad alternator early can save you from being stranded on the side of the road. Here are the most common signs to watch for:
- Dim or Flickering Lights: If your headlights or interior lights are dimming or flickering, it could indicate that the alternator isn’t supplying enough power.
- Battery Warning Light: The battery warning light on your dashboard may illuminate if the alternator is not charging the battery properly.
- Dead Battery: A failing alternator can’t recharge the battery, leading to frequent dead battery issues even after jump-starting.
- Strange Noises: A worn-out alternator may produce grinding or whining noises due to damaged bearings or internal components.
- Electrical Failures: Malfunctioning power windows, radio, or other electrical systems can be a sign of insufficient power from the alternator.
- Burning Smell: Overheating alternators can emit a burning rubber or electrical smell, often caused by a slipping belt or internal failure.
How to Confirm the Problem
If you suspect your Subaru’s alternator is failing, here are some steps you can take to confirm the issue:
- Check the Battery: Use a multimeter to test the battery voltage. A fully charged battery should read around 12.6 volts when the engine is off. If the voltage drops significantly while the engine is running, the alternator may not be charging properly.
- Inspect the Alternator Belt: Look for signs of wear, cracks, or looseness in the alternator belt. A damaged or slipping belt can prevent the alternator from functioning correctly.
- Listen for Noises: Start the engine and listen for unusual sounds coming from the alternator. Grinding or whining noises often indicate internal damage.
- Test the Alternator Output: A professional mechanic can perform an alternator output test to determine if it’s generating the correct voltage and amperage.
What to Do If Your Alternator Is Bad
If you’ve determined that your Subaru’s alternator is failing, it’s important to address the issue promptly. Here’s what you can do:
- Replace the Alternator: A faulty alternator will need to be replaced. This is a job best left to a professional mechanic unless you have the tools and expertise to do it yourself.
- Check the Battery: A failing alternator can damage the battery, so it’s a good idea to test the battery and replace it if necessary.
- Inspect Related Components: Ensure that the alternator belt, tensioner, and electrical connections are in good condition to prevent future issues.
Preventative Maintenance Tips
To avoid alternator problems in the future, follow these maintenance tips:
- Regularly inspect the alternator belt for wear and tension.
- Keep the battery terminals clean and free of corrosion.
- Have your electrical system checked during routine maintenance visits.
- Replace the alternator at the first sign of failure to prevent further damage to your vehicle.
Conclusion
A failing alternator can cause significant inconvenience and potentially leave you stranded. By recognizing the warning signs and addressing the issue promptly, you can keep your Subaru running smoothly. If you’re unsure about diagnosing or replacing the alternator, don’t hesitate to bring your vehicle to a trusted auto repair shop like Kevin’s Autos. With years of experience in car maintenance and repair, we’re here to help you get back on the road safely.
Frequently Asked Questions
How do I know if I need a new alternator or battery?
One of the most obvious signs is if the car dies after a jump start. The alternator should provide enough current to keep the vehicle running even with a bad battery. If it doesn't, then your alternator needs to be examined.
How long do Subaru alternators last?
How Long Do Subaru Alternators Last? Subaru alternators typically last around seven years or more, often exceeding 100,000 miles.
How does a vehicle act when the alternator is going out?
And interior lighting if the lights brighten as rpms. Increase that is a telltale sign of a failing alternator.
Will a bad alternator cause rough idle?
Yes, a bad alternator can indeed cause a rough idle.
How much does an alternator cost Subaru?
The average cost for alternator replacement is $747 to $842.
How can I test my alternator?
Use a multimeter to test the voltage coming directly from the alternator with the engine off and running. To do this, attach the red probe to the output terminal on the back of the alternator and the black probe to the ground. With the engine off, you should get a reading around 12 volts.
What are the first signs of an alternator going bad?
Some warning signs of a failing alternator include:
- Trouble starting your car.
- Frequent stalling.
- Whining or screeching noise after the vehicle starts.
- Dim or overly bright lights.
- Smell of burning rubber or wires.
- Dead battery.
- Battery dashboard warning light is on.
Can AutoZone test an alternator?
Getting your alternator tested at AutoZone is simple and hassle-free. An AutoZoner can test your alternator while its still in your vehicle, saving you the hassle of removing it and re-installing it if it's still good. Or, if you have the alternator out of your vehicle already, we can test it on the bench instead.
How do I know if I need to replace my alternator?
7 Common Signs Your Vehicle Needs an Alternator Repair
- Starting Problems or Frequent Stalling.
- Warning Light Illuminates.
- Headlights Are Either Too Faint or Too Bright.
- Poorly Charged Car Battery.
- Burning Smell.
- Electronic Features Malfunction.
- Growling Sounds.
How do I know if my Subaru alternator is bad?
The Car Stalls
When you're driving and all of a sudden your engine stalls, it's likely that there's a problem with your alternator. This is because when your alternator fails, it cuts off power to some of your car's systems, including those that keep your engine running smoothly.
