Your car won't start and you want change the battery by yourself? It is not a complicated operation, but you must take into account a series of steps that must be carried out. In old cars it is very simple, but in modern ones it is It is important to change the battery carrying out a series of recommendations. The reason is that today's cars have a lot of electronics and control units.
The first thing we think when the car does not start is that the battery has run out. We may be right. However, this may not be the reason. You have to make sure. There may be an electrical problem, an issue with the glow plugs (diesel car heaters) or even an anomaly in any sensor or component that the system recognizes and therefore does not allow the engine to start.
Step-by-step explanatory video
Each model has its peculiarities, but all 12V batteries require the same basic knowledge to be able to change them. In this video We teach you how to do it following a few simple steps, including the option not to lose memories. An especially important detail in modern cars.
How to know if you need to change the car battery
As I said above, the first thing is make sure that the problem actually comes from the battery, that it is exhausted. It is important not to force too much trying to start. If we hit the starter a couple of times and the car doesn't start, better stop trying.
One option is use a voltmeter to measure the tension. We click on the positive and negative poles and if it gives us a lower voltage, it approaches 12 volts from above, it is practically certain that the car battery is ready to change. However, to do it right, you better take a look at the following video:
Symptom
In any case, if we use the car almost daily, as a general rule we can noticing symptoms that the battery is running low. The symptom that the battery is about to change is that we must use the starter for several seconds and, also, that the speed of rotation of the starter motor is slower than usual.
On the other hand, and although depending on the vehicles, it is possible that the instrument panel needles make improper movements during the starting phase. There are times when they go up or down suddenly. Finally, on some models it is also easy for the instrument panel lights to vary in intensity.
Unfortunately, in current cars the symptoms are becoming less noticeable. In fact, in the latest cars, the most normal thing is that it starts as usual every day and there comes a day when it does not even make the gesture of trying to move the starter motor.
How often is it normal to change the battery?
Many times we wonder how often it is normal to replace the car battery. The truth is that it depends a lot. What is certain is that, as a general rule, the vehicle's original battery lasts longer. It is easy to hear cases of serial batteries that have lasted 8 or even 10 years. This is because spark plugs or heaters, injectors and other components are in better condition when the car is new than when they are many years old.
La battery durability, as we said before, It depends a lot on the type of use and the weather conditions.. Firstly, in cold temperatures, the starter motor has to work harder to fire up the heat engine, putting more strain on the battery. Likewise the short trips reduce durability of the same, as well as driving at night by having the lights constantly on. Also the use of the fog lights or the heated rear window, which consume a lot of energy.
What if it is downloaded before?
A battery can deteriorate prematurely if the car is not used for a long period. The alternator does not have a chance to charge it again and it loses energy until it is completely discharged. Which usually means early battery degradation.
Another possible cause why it will download early is that the vehicle has a current leak. What can happen when you have a deteriorated or poorly mounted electrical component. In the next video you can see how it is easily checked, to know if that is the case with your car:
Steps to change the car battery
locate the battery
Although it is better explained in the video above, we also leave it in writing. Once we are clear that the problem is that the battery has run out and needs to be replaced, the first step is to locate it. The vast majority of cars have it in the engine compartment; but there are some models that place it in the trunk, under its floor.
Roll down the windows
It is important to leave the windows down and make sure that the car is open. It is a measure to avoid scares. If you have the car closed and the windows up, when you disconnect the battery you may find yourself with a new problem that does not interest you. Yes, you can find yourself with the car locked. However, if this happens, you can always open the driver's door with the key.
Disconnect the terminals
It is time to disconnect the terminals, but we do not have to remove the one we want first. First we must remove the negative terminal (black color and marked with a “-“) and then we remove the positive (red color and marked with “+”). To do this you have to loosen some clamps. In case of doing it in the opposite way, we can create a short circuit with the tool itself, which can lead to breakdowns.
Take out the car battery
The last step in removal is to loosen the locking system on the battery itself. The battery is a heavy component and therefore it is well secured, usually with a plate and a screw, although there may be more systems. This is so to prevent it from moving and causing problems in the event of braking or impact. Once “unlocked”, we simply extract it. Of course, keep in mind that it weighs, you can hurt your back.
Install the new battery by reversing the steps above
Then we put the new battery in place and secure it with the immobilization system described above. Subsequently We connect the terminals by first plugging the positive “+” and then the negative “-”, making sure to tighten them well.
To start the engine
Finally, we check if the heat engine starts. If we have bought the right battery for our vehicle, everything should be fine. Once started, if we have not used a memory preserver, it is important to make the relevant settings in the car again, such as the comfort function of the electric windows, the time or the memories in the radio stations, as well as our preferences in the infotainment system.
Change the battery of a modern car
If we are talking about a very modern vehicle, the steps to follow when replacing the battery are those mentioned above, except if it is a hybrid car. In this case, honestly, it is better not to complicate your life and take it to the official dealer, since in some cases they must connect a diagnostic machine during the operation. This is because they have many more electronic systems and can also be more sensitive to possible voltage spikes.
In the event that it is not a hybrid but it is a modern car, the ideal is to use a small battery to prevent the car from losing all its memories. More than anything because in addition to the fact that some systems such as the radio can be blocked, it is very possible that numerous faults will also light up on the instrument panel that will force the car to the workshop to connect the diagnosis and erase them. This small auxiliary battery is known as a memory recorder or memory preserver. I will explain it to you in the next section.
Change car battery without losing memory
One of the problems with changing the battery is that some electronic systems must always have a little power, even when the car is off. Logically, when we change the battery, this voltage is eliminated, which means that these systems are deprogrammed.
Radio memories, infotainment settings, power window comfort function, ESP problems, and in some cases (particularly in cars from a decade or two ago), radio lock.
To avoid changing the battery without deconfiguring the computer, connect a small auxiliary battery. Although it is of low capacity, since the car will be turned off, its only effort is to keep those memories for a few minutes, a task that it will be able to carry out. Thus, we will replace the battery without losing the saved data.
These batteries, known as memory recorders or memory preservers -like this-, they are connected to an accessory socket or to the car's own cigarette lighter. Its price is around 15 euros.
How much does it cost to change a car battery?
If we do it on our own, it's basically the cost of the battery. As a general rule, the tools to replace the car battery are basic. With a pair of fixed keys and perhaps a ratchet with an extension to release the fastening to the car is enough. Yes it is it is important to protect ourselves with gloves to avoid blows, cuts or staining ourselves with the acid of the same. By the way, I remind you that we must avoid turning the battery over or touching our clothes, since the acid can spill and spoil those jeans or that precious shirt.
Regarding the price, it depends on the vehicle. We can find cheap batteries for 60 euros or we can go up to 150 euros if it is a diesel car, modern and powerful. The cheapest are those of gasoline cars with little displacement and performance, such as 1-liter engines without turbo. On the contrary, you can already imagine that a 3.0-liter diesel with a lot of technology and start & stop will need much more capacity.
What battery does my car have?
To find out which battery a vehicle has, you can look at the one you are going to remove, since it is usually put on a sticker on the top or engraved on its own casing. If it is not the original battery and/or if the car is second hand, the best and most efficient is take a look at the manufacturer's manual. It will show us where to put the poles to match our vehicle (there are batteries with a positive pole on the left and others on the right), the voltage (V), the intensity (A) and the capacity (Ah).
El voltage is the tension. Cars use 12 volts (trucks at 24 and some motorcycles at 6), so in that sense there is no need to fear making a mistake. The intensity (A) is the force that it is capable of giving for a few seconds, the intensity at the start. In diesel mechanics, more intensity is needed than in gasoline ones due to the consumption of the preheaters and, above all, due to the greater compression in the cylinders. There are car batteries from 300 A to about 900 A. Lastly, the capacity It is measured in amps/hour (Ah). If it says 62 Ah, it means that if it had a 62 amp consumer it would take an hour to fully discharge.
