Ground wires for car batteries are typically attached to the negative terminal on the battery. If you are having trouble locating the negative terminal on the battery, make sure to check the car manufacturer’s manual for specific instructions. The negative terminal will typically be marked with a “-” or a “NEG”.
Once you have identified the negative terminal, simply attach the ground wire to the negative terminal. It’s always important to make sure the connection is secure before turning on the vehicle or attempting to start it. The ground wire should be attached to a metal part on the car chassis or engine block. A screw or bolt can be used to secure the ground wire in place, but it’s important to ensure that it’s a good, sturdy connection. Once the ground wire is in place, you can go ahead and start the car or turn on the ignition.