1. Look for the plus (+) and minus (-) symbols on the battery terminals. These symbols are usually stamped into the metal of the terminals, or they may be printed on a sticker or label attached to the battery.
2. If there are no plus and minus symbols on the battery terminals, you can use a voltmeter to determine which terminal is positive and which is negative. To do this, connect the positive lead of the voltmeter to one terminal and the negative lead of the voltmeter to the other terminal. If the voltmeter reads a positive voltage, then the terminal that the positive lead is connected to is the positive terminal. If the voltmeter reads a negative voltage, then the terminal that the positive lead is connected to is the negative terminal.
3. You can also use a simple trick to determine which terminal is positive and which is negative. Wet your fingers and touch the terminals. The terminal that feels hot is the positive terminal. The terminal that feels cold is the negative terminal.
Note: Be sure to disconnect the negative battery terminal before working on your car's electrical system. This will help prevent any electrical shocks.
