Do you need to charge battery after replacing alternator?

You should charge your battery while your replacing the alternator. Then after it’s charged it should be load tested to see if it’s good or not.

What would cause an alternator to surge?

Improperly jump-starting the vehicle can send a surge through the battery that destroys one or more cells in the battery or shorts it out. This surge disrupts the wiring in the alternator, causing an overcharging condition.

Why is my brand new alternator not charging my brand new battery?

The most obvious reason why your battery won’t charge when your alternator is brand-new is that the problem is with the battery itself. If you’re not 100% sure, you can use a multimeter, or a voltmeter, to check the current coming from your battery.

How long does it take a battery to charge after replacing alternator?

Basically, at idle you can probably get 80 amps out of your alternator. You can charge a flat battery to 80 percent full in about 2 hours, so long as you alternator can manage produce around 14 volts at the battery terminals this whole time.

Can you fix an overcharging alternator?

Temporarily, the problem can be fixed by manually cutting the small positive wire that supplies power to the field windings of the alternator…. By putting a switch in between to interrupt the over charging…. Every so often to avoid damaging the battery ……

How do I fix my alternator not charging?

Check the large power cable to the alternator and the fuse, usually, a large 40-60 amp fuse near the battery. Check the ground cable between the engine and the body. Check the serpentine belt and make sure the alternator is spinning with the engine. Check the small power supply wire and the charging light wire.

Can a bad alternator ruin a brand new battery?

Can a bad alternator kill a new battery? Yes, very easily. A failing alternator can overcharge, which will damage the battery. An undercharging alternator will leave the battery flat, which speeds up its failure.

Does alternator charge battery at idle?

Do Car Batteries Charge While the Engine Is Idling? The answer is ‘YES’, yes the car battery does charge while the engine is idling. Then the alternator is producing AC current, thereby charging the battery while your car is idling.

What happens if you have a new alternator and the battery is not charging?

The alternator in your car is an integral part of your vehicle’s electrical system. If you have a new alternator and the battery is still not charging, then you definitely have some kind of a problem with your battery that you’ll need to address immediately.

How do I know if it’s the battery or the alternator?

Both of these car parts control your electrical system. However, your alternator charges your battery while your battery supplies power to your car. The failures of a battery are sudden, while failures of a failing alternator are slow. Always check your battery first, it can generally tell you which of these two is the culprit.

How does an alternator tester work on a car?

First, a battery tester will be used to confirm if the battery is still capable of holding a charge, or if it has dead cells and must be replaced. Once the battery has been either recharged or replaced, the output of the alternator is checked with a multimeter.

What should I do if my alternator keeps dying?

The alternator is essentially a generator and it keeps your battery charged while supplying additional electrical power for the other systems in the vehicle. If you have a new alternator and your battery keeps dying on you, then there’s definitely a problem that you’re going to need to look into.

What to do if your alternator is over charging the battery?

Ask an assistant to start the engine and hold engine speed at about 1500 RPM. 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.

How can I tell if my alternator is working or not?

If you’re not 100% sure, you can use a multimeter, or a voltmeter, to check the current coming from your battery. Attach the positive lead to the positive battery terminal, that’s the red one, and then the negative leave it to the black terminal. With the engine off you should be getting a reading of 12.5 volts on your multimeter.

How does an alternator and battery work together?

Anything less than that and your car isn’t even able to start. Both of these car parts control your electrical system. However, your alternator charges your battery while your battery supplies power to your car. The failures of a battery are sudden, while failures of a failing alternator are slow.

Why does my alternator get higher than base voltage?

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.