My car battery low voltage, what this mean?
A car battery holds important functions to make all-electric systems work properly. It powers the vehicle to start up the engine and serves electricity for all the electronics equipment inside it. The car's battery can function properly if it still has these two things, amperage, and voltage. If one of these two things is in poor condition, runs out, or is low, you will face some problems with your car.
It's important to test your car battery and electrical system regularly. Twice a year is an ideal time to reduce your chances of car failure because of the battery. If you regularly visit the auto shop, you can ask the mechanic to check the battery's condition and its performance. However, if you cannot go to the workshop, you can check your car battery using voltmeter to test car battery.
Make sure to turn off the ignition and all electronic components and turn on the multimeter. Pointed the voltmeter's selector on the DC volt measurement (for analog multimeter, put it on 50 DC volt range). Then connect the lead with a red color probe from the multimeter to the plus battery (positive terminal) and the black color probe to the battery's negative terminal.
If you get a negative voltage reading, that means you have swapped the leads on the voltmeter. Swap them back, and you'll get an accurate reading.
Car battery voltage range
Conducting a voltage test with a voltmeter on your car's battery can be a great way to determine its performance. There are two conditions to measure your car's battery. The first is with engine OFF (it means your car engine is in OFF/STOP condition), and the second is with a running engine.
The off position measures the battery voltage itself, while the running engine measures the charging system voltage. Here are some recap for the car battery voltage chart
Car battery voltage chart when the engine is OFF
| Battery condition | Engine OFF (stop) |
|---|---|
| Fully charge (Good) | ⩾12.6 Volt |
| Fair to use | 12-12.5 Volt |
| Low voltage | 11.8-12 Volt |
| Discharge | ⩽11.8 Volt |
Car battery voltage chart when the engine is running
| Battery condition | Engine ON (running) |
|---|---|
| Fully charge (Good) | 14.8 Volt |
| Good | 14.4 Volt |
| Fair | 13.4 Volt |
| Check !! | 13.2 Volt |
Car battery voltage range means
Below is the explanation af the battery voltage range that you can use as a common car battery voltage reference.
Fully charge battery
What voltage should my car battery be? It is a common question to know what is normal car battery voltage. As you can see from the table above, a fully charged car battery voltage will show more than 12.6 Volt or above with an OFF engine.
When the engine is turned ON (running engine), the measurement voltage would rise to 13.4 -14.8 Volt. This voltage increases due to the charging system (Alternator) is working. This result means your car's battery is in good condition, and the charging system works fine.
When the voltage is below 13.2 Volt while the engine is running, it's a sign that your charging system performance starts to decline and needs attention. It's better to be done by a certified mechanic to check all the charging systems and the battery.
Fair to use battery
Fair to use battery voltage is in between 12-12.5 Volt. It means your car battery is in a fair-to-use condition and still able to work properly. It is the low state of the battery voltage that starts the engine. So, to answer how many volts does a car battery need to start is 12-12.5 Volt. Lower than that, your car battery may difficult to start the vehicle.
Decreasing the value of battery voltage can be caused by a variety of things ranging from the battery's lifespan to the condition of the liquid and battery elements where the condition has also decreased.
Read also :Low voltage battery
Low voltage battery is in between 11.8-12 Volt. The low voltage battery means you should prepare for a recharge battery or do a battery replacement (depends on the overall battery conditions). When your car battery low voltage, sometimes it works to start the vehicle, but it's more often fails.
This condition generally occurs from several causes such as:
- Old battery (worn battery element and liquid)
- Bad connection to the battery terminal
- Alternator undercharge
Discharge battery
The discharged battery shows a voltage of less than 11.8 Volt. Mostly, we can't use the discharge battery to start the engine.The engine won't start and just a clicking noise. You can recharge this discharge battery with charging equipment, but it won't be helpful for a longer time. The only way is to replace the battery indeed with the new ones. Yes, discharge battery can be a sign of a dying battery.
Testing a car battery with a voltmeter only cannot be used as a primary benchmark to determine whether the battery is suitable for use or must be replaced.
Because to determine the battery is good or not, you must carry out several advanced battery measurements. Such as measuring battery voltage loads, Cold Crank Ampere measurement, and or battery liquid test (for typical wet battery). All the battery tests require some special tools that may not be available in your home at the time.