Understanding your vehicle’s electrical system is a key part of effective car maintenance, and one of the crucial aspects is knowing what the voltage should be.
Whether you are trying to charge your battery, or troubleshoot issues with a dead one, keeping it working effectively is essential for overall car health.
In this guide, we explain what your voltage should be when it is off, idling and running – and other helpful tips to keep your battery in perfect working order.
What is car battery voltage?
Car battery voltage is the electrical potential provided by the vehicle’s battery and alternator and is measured in volts.
The majority of modern vehicles has a 12-volt battery which powers most components in the car, including the starter motor, ignition, dashboard, headlights, entertainment system, and the on-board computer system.
As a general rule, car owners should regularly have their car battery checked during a service.
What is voltage?
Voltage is the measure of electrical potential between two points in a circuit, and is essential to push electricity through wires and components.
Weak voltage means that there isn’t enough power going to the end of the wires, and too much voltage can overpower it and break the system.
What voltage should a car battery be?
Depending on the state of the vehicle the car battery should have different voltage. If this isn’t the case, then there could be an issue with it.
Off
When the engine isn’t on, a car battery should have a voltage of around 12.6 volts.
Idling
Once the engine is running – but the car isn’t moving – then the car battery should have a voltage between 13.7 and 14.7 volts.
Running
After the driver has pulled away and the car is moving, the battery should still have the voltage between 13.7 and 14.7 volts.
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