Red is usually battery positive.
disconnect the negative (black) first then positive (red).
The black wire means negative and the red wire means positive if that's what you where asking
On the car battery, the positive wire is red and the negative wire is black. If the body of the car is metal or conducts electricity, then the body of the car serves as the negative wire. The metal in the engine serves as the negative wire.
get a multi meter that reads dc voltage & touch the black (negative -) wire to the negative battery post & the red (positive +) wire to the positive battery post with car running. car off is battery voltage, car on is alternator voltage.
once a battery is connected even if the key is not in the ignition, there is always power at certain points in your car. Connecting a battery backwards will not start your car, but it can and will fry the wires to your starter.
The electrode with the + mark, red wire. Black is negative.
The red battery wire goes on the positive + battery terminal no matter which side it is on. The black wire goes on the negative - terminal.
Negative - (Black) is Ground, Positive + (Red) is Hot. Ground wire goes to Negative (Black) it goes from negative on battery to engine for ground.
Red wire is Positive in a car battery. If they are not color coded, find which one is not connected to the chassis and this will be positive.
Put the solar panel in the sun;Attach the red wire of the panel to the positive terminal of the battery;Attach the black wire of the panel to the negative terminal.
RED wire goes on +, and the black wire gets wired to the body of the car. Which is ground -
The starter is located in fromt of the car on the bottom. Follow the red wire from the battery.