Can a bad alternator kill a good battery?
Can a bad alternator kill a good battery?
Bad alternators can absolutely kill a good battery. There are two ways that it can do this. First, your alternator might not shut off and end up overloading the battery with too much voltage. Conversely, it might not charge the battery at all.
What causes an alternator to over charge a battery?
Measure voltage across the battery with your DMM. You should get 0.5 to 2 volts higher than base voltage. If you are getting more than 2 volts above base voltage, most likely your alternator is over-charging the battery or the battery is faulty. Other potential problems are a faulty voltage regulator or a problem in the charging system wiring.
What should the voltage of an alternator be?
Connect the other lead to a good ground (the negative post on the battery is a great choice!). Your alternator should be putting out between 13.5 to 15 volts. Anything less than this, and you have a bad alternator! If your alternator is putting out this voltage, then something else is killing your battery.
How long should an alternator last in a car?
Unlike components such as your oil filter or your water pump, the alternator should last if not the life of your vehicle then definitely a significant amount of time. A good alternator and can last well over a decade, sometimes as long as 15 to 20 years.
Can a battery run down with no alternator?
An alternator that’s not providing enough power can allow a battery to run down. According to Prestolite electric, an alternator producing less than 13.8 volts of power at idle is not producing enough current to charge the battery fully and needs to be replaced.
What should the voltage of the alternator be?
What is the output of your alternator? Battery voltage measured at the terminals with the engine running should be about 13.7-14.7 volts. That is the output of the alternator at the battery and that range is needed to keep the battery properly-maintained.
Can you run an underdrive pulley on an alternator?
If you are running an underdrive pulley, there’s a good chance your alternator will never be able to properly-maintain voltage in your battery and keeping your vehicle plugged in to a quality battery charger will have to be a part of your regular routine. Is your wiring and grounds in good shape?
Can a bad belt affect the alternator and battery?
However, if the belt or a tensioner pulley on the belt is damaged or not functioning properly, it could negatively-impact both the alternator and the battery, neither of which may have any problems of their own.
What can I do if my car battery keeps dying?
To check cold-cranking amps, you need a specialty tool. The good news is that you can take your car to AutoZone and they will test and charge your battery for free. Check the alternator. Yes, you think it’s okay, but did you check it the right way?
How can I find out if my car battery is draining?
In most cases, the only way to track down a parasitic drain is through a process of elimination. The easiest way to go about this type of diagnostic is to leave your multimeter or test light connected and remove individual fuses until the drain disappears.
How can I tell if my battery needs to be replaced?
If one or more cells is very low after fully charging the battery, that’s a sign that the battery needs to be replaced. Another way to check your battery is to use a more expensive tool called a load tester.
How can you tell when your car battery is dying?
You may be able to tell when your car battery starts to die if you find it difficult to start, have flickering lights, or a weakening alarm system 1. Human Error
How can you tell if it’s the alternator or the battery?
Having the battery tested is an easier proposition, but either test will isolate those two components and offer definitive confirmation as to whether or not they are the source of your issues.
What to do if your car battery is draining?
Assuming that the cause of the battery drain is not human error, you will need the assistance of a qualified mechanic who can diagnose your car’s electrical problems and determine if it’s a dead battery or something else in the electrical system.
Why does my car battery keep dying when I Turn Off the engine?
Your engine’s serpentine belt powers your alternator – so after you shut off the engine, your alternator isn’t working. So, if something is using power, your battery isn’t getting recharged. This could be as simple as forgetting to turn off your headlights or radio – something more complicated like your ECU not powering down.
