What should I do if my car battery is getting weak?

Most people will have trouble determining whether a car battery is dead or simply discharged. You simply feel the consequences, which can be severe, since without a functioning battery a car will not start, and if you have an important appointment to get to it can be a major headache. A dead battery must be replaced with a new one. If the voltage of a battery is between 9-12 volts, it is merely partially discharged and not irreversibly damaged. The reading under load, the so-called high-current test, in most cases can be performed only by a battery specialist or workshop.

Repairing a car battery

The trend is moving increasingly from low-maintenance to maintenance-free batteries. However, there are a few cases in which you can repair a battery. With a maintenance-free battery, due to the lack of a filling tube for distilled water, there is not much chance of repairing it. But you can open the top of a low-maintenance battery and check the fill level at least yearly (while wearing safety glasses). Topping off the level until the lead plates are fully covered with water helps to prevent the battery from drying out. You can remedy a flickering battery light with new carbon rods for the battery controller module. You can buy the parts for around 30 Euros.

Repair alternatives for a faulty battery:

• Reviving
• Jump-starting
• Disconnecting
• Changing

Reviving

If the car is slow to start, then it's definitely time to revive the battery. For this you should connect a commercially available charger to the battery and recharge it. If nothing else helps, you can also try a special device called Megapulse. This was tested by TU Vienna and it was found that all old batteries tested were able to regain their charge capacity after a treatment with the Megapulse device, even if the batteries showed a medium to high level of damage before the test. To destroy the harmful lead sulfate crystals in the battery, the device delivers constant high-frequency current impulses to the battery to revive it.

Jump-starting

During the life of an automobile, practically every driver has to jump-start their battery to get it going. In cold temperatures during winter, the battery has to work very hard, and so the risk increases greatly that the car will not start, especially during the cold season. Properly jump-starting the battery is not difficult:

1. The car with the dead battery is the receiving vehicle. The car with the good battery is the charging vehicle. Both vehicles should operate on the same voltage, usually 12 V.
2. The engine on the charging vehicle is turned off, and power-draining components like air conditioning, etc. are also turned off on both vehicles.
3. One end of the red cable is connected to the positive terminal of the receiver, then the other end is connected to the positive terminal of the charging vehicle.
4. The end of the black cable is connected to the negative terminal of the charging vehicle and then the other end is connected to a bare spot on the engine block of the receiving vehicle.
5. The engine of the charging vehicle is started, and then the receiving vehicle can briefly try to start the engine. If it starts, it simply can be kept running. If it does not start, try again.
6. After successfully starting the car, first disconnect the black negative cable and the the red positive cable.

Disconnecting

If your vehicle is slow to start or doesn't start at all in winter, it's time to change the starter battery. To do that, you first have to remove the old battery, but with our tips just about anyone can do it. This is one of the simplest maintenance tasks you can quite easily do yourself without going to a mechanic, an unnecessary expense. You should then invest the amount you save in a good-quality battery, so that your car will start reliably in cold temperatures. If the starter battery is so weak that the car simply will not start, you will have to disconnect the battery and either charge it fully, or if that does not work, replace it. Then it comes down to following the steps required to do the job. These are important:

• If your car stereo can only be reactivated by entering a code, be sure that you know the correct code. Otherwise there will be very little hope of getting your radio working again afterwards.
• There is a proper sequence for disconnecting the battery: First disconnect the cable from the negative terminal, and be careful not to let it touch the terminal after removing it. Then remove the cable from the positive terminal in the same way.
• After removing the cable, the battery holder can be opened and you can remove the battery.
• You may have to re-program the radio presets after changing the battery.

Changing

The many devices in modern cars that use electricity will drain the battery's power. In cold seasons many starter batteries will simply die. At the very latest, needless to say, this is the time to have the battery changed or do it yourself. But you don't have to go to an expensive mechanic; if you follow a few important guidelines, changing the battery is no problem at all. With the following step-by-step guide you can quickly change a battery yourself:

1. Before beginning, be sure that the engine and all power-using components like the ignition are completely turned off! It's important above all that the radio, onboard computer, and navigation system are also off; otherwise when disconnecting the power with a reset, all previous settings will be lost.
2. Now open the hood and loosen the cable clamp on the negative terminal with a properly sized screwdriver or wrench, as applicable. Then remove the cable and secure it so that it cannot touch either the battery or the positive terminal, so you avoid causing sparks or a short circuit.
3. Now you can loosen and remove the cable on the positive terminal. Also here, be very careful that the cable connection does not touch the battery or the negative terminal.
4. With a suitable screwdriver, wrench, or ratchet/socket, remove the bracket screws holding the battery in the battery compartment. Then you can lift out the old battery. You'll then place the new starter battery into the battery compartment and fix it into place.
5. Now connect both cable clamps, in reverse order this time: always connect the positive terminal first and then the negative. Finally, protect both terminals with an appropriate terminal grease or spray. This protects them over the long term from corrosion and oxidation.

Short circuit

Acar battery short circuit is not only hazardous to the battery, but also for all the onboard electronics, since in a short time the resulting increased voltage will course through all the devices connected to the electrical system and can cause severe damage. To avoid short circuits, you must avoid accidentally reversing the cables. Never allow anything to connect the positive and negative terminals. Even if the terminals have slightly different diameters, you can nonetheless touch both cables to the contacts at the same time, thus causing a short circuit. When connecting a new battery, always be careful and thoroughly read the instructions before installing.