When Does A Car Battery Have Voltage But No Amps? What’s The Solution?

We may face different problems with our car batteries once in a while. One of the many problems is no amps on the battery even though it shows voltage in the reading. 

Another question that you may ask regarding the problem is – “can a car battery have a high voltage and yet be defective?’

The answer is yes! It is possible. A good battery ought to be slightly higher than 12 volts at rest and climb to around 13.5 volts when charged. The voltage of a battery under load is its evidence.

Why do I have voltage but no amps in the battery?

A faulty connection anywhere between the rectifier and the load is by far the most typical reason for no amperage.

Test the voltage across the load and the anode bar to see if this is the situation.

When there is hardly any voltage, there is a faulty connection somewhere, and you must locate and repair it.

What causes voltage loss in a circuit?

Excessive dropping is produced by higher resistance in a circuit, which is usually generated by a higher load, or energy consumed to power electric lighting, in the form of more connections, elements, or high-resistance conductors. 

Nevertheless, while understanding or limiting voltage drop, the applied power, wire size, and wire length are all significant aspects to consider.

For instance, greater gauge (thinner) lengthier wires will decrease at a higher rate than shorter wires with a lower gauge (thicker). This is since the resistance of a wire is proportional to its cross-sectional area over a given distance.

If there is a greater distance for the electricity to go or a smaller cross-section for this to pass through, the electrical impedance of a wire or cable rises, but shorter cables have less resistance to electrical current since the current has a shorter distance to cover.

Lower gauge wire has a bigger cross-section, which increases the surface size for electrical conductivity. When it comes to lighting, the closer light fixtures are to the utility transformer or power provider, the stronger your lights may be.

Not only do more weights or components increase distance, but they also increase resistance. Another thing to keep in mind is that only the elements that use or burn energy need to use energy.

How many amps is a 12-volt car battery?

Car batteries have a usual output of 48-amp hours. This implies that a completely charged 12-volt automobile battery with a capacity of 48-amp hours may provide 1 amp for 48 hours or 2 amps for 24 hours.

This also indicates that under optimum working conditions, the battery can provide 8 amps for 6 hours.

Can a dead battery still show 12 volts?

Yes, a battery may have 12 volts and still be defective. A lot is riding on the volts your vehicle battery or any battery displays. It tells if the battery is good or poor, and the volt can tell you how charged the battery is.

How? I’d describe this voltage in terms of science so you could grasp it.

Voltage in a battery refers to the variation in electric potential among the battery’s two terminals (negative and positive).

The standard motorized battery in a modern automobile is a 12-volt battery. A battery has 6 cells, plus one cell that contains 2.1 volts when the battery is fully charged.

Furthermore, after verifying the voltages after the battery is completely charged, make sure to load test it. This would allow you to become more aware of your battery’s status sooner.

Furthermore, even if your battery shows 12 volts, there are a few techniques to tell whether it is faulty.

Can a battery have good voltage but still be bad?

Indeed, a battery can have a high voltage and still be defective. When you want to utilize your battery, it should display the correct 12.6 volts and switch off. This is why, after testing the voltage, you should do a load test on your battery. The load test will tell you whether or not your battery is bad.

Whenever your battery dips below 8 volts throughout the load test, it is faulty. Nevertheless, make sure the battery is completely charged before performing this test.

Whenever the voltage under load is 11 or 12.3 volts, the battery is good.

Thus, you may have observed that expert vehicle mechanics not only test for battery voltage but also start the car to ensure the battery is in good enough condition for you to use.

Launching the automobile is a method of putting a strain on the battery, as well as turning on various other components in the car.

Even if the battery reduces dramatically when subjected to a load, this does not always imply that everything is lost. You may just have to charge the battery until it is fully charged before you can use it.

How do I test a car battery amp with a multimeter?

In case you need to check if you have an amp or the amount of it you can use a multimeter to find it out. Here is how you should use it-

Step 1:

Check that the ignition, lights, and radio are all turned off.

Choose the DC volts option on the multimeter. DC voltage is typically represented by a V trailed by a short line with something like a dotted line beneath it.

The wavy line following a V represents alternating current voltage and is used to test the mains voltage in your home.

The majority of manual ranging meters offer a 20V range, which really is sufficient for testing a car battery. This should read between 0V and 20V because it is in the 20V range.

Step 2:

With the red lead connected into the voltage (main) circuit of the multimeter and the black wire connected to the common (COM) terminal of the multimeter, connect the red wire to the positive (+, generally red) terminal and the black wire to the negative (—, usually black) terminal of the battery.

Step 3:

The meter, therefore, is linked in parallel with the automobile battery and will immediately display a measurement.

Take note of the DC volts measurement and relate it to the table below, which shows the charge state under no-load:

Car batteries deliver 12.6V DC (direct current) via six cells that produce 2.1V apiece.

-12.6V: fully charged

-12.4V: 75% charge

-12.2V: 50%

-12V: 25%

-11.9V and below: effectively zero charge

Step 4:

Anything less than a 75 percent charge rate, or around 12.45V, often indicates that the battery is below-charged and needs to be recharged.

It will not, nevertheless, imply that it is harmful. If it doesn’t keep a charge after recharging, it’s likely on its way out.

Step 5:

Recharge it when it is less than 12.45V. This may be accomplished with a portable charger hooked into the mains, that will deliver progressive current over time.

The second alternative is to drive for approximately 30 minutes. It is important to note that simply starting the engine and letting it rest will not result in a good charge from the alternator.

Another alternative is to charge the battery at a nearby auto repair shop.

After charging, repeat the previous test to verify if the battery now reads in the 12.6V range. Or else, consider having it thoroughly inspected before replacing it.

Conclusion

Having no amp on the battery may indicate a failure or problem in your battery. If you can figure out the problem and have knowledge about how to solve it, you can repair it. Otherwise, it is best to take it to an expert or buy a new one.

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