Car audio wiring installation is not as difficult as it seems. The hardest part involves determining which wires are which. Once this is overcome, the remainder of the installation is straightforward.
You will need: the car audio, a snap-on wire harness, a Phillips No. 2 screwdriver, an 8mm socket, a solder/crimper, a voltage meter and a small battery. The battery will be used to test the speaker wires, the voltage meter will be used to make sure that the voltage is between 10 and 14 volts and the crimp will be used to make the wire connections.
Removing Old Radio
Remove the screws that secure the plastic panel on the radio. Remove the plastic panel by lifting the bottom of the panel and pulling outward. Then remove the screw bolts and unplug both the black cable and plastic wire harness connectors from the rear of the radio.
The radio will be plugged into the antenna cable. Place the new radio in the dash and make sure that metal brackets are aligned to the mounting locations. Screw the bolts into the screw holes. Replace the plastic panel and screw it back in.
The wires will consist of the ground wire, the +12-volt battery wire, the +12-volt ignition wire, the power antenna wire, the left front speaker wires, the right front speaker wires, the left rear speaker wires and the right rear speaker wires. The old wires can be connected to the new wires by using a snap-on wire harness. These wires can also be connected by splicing the wires. These wires will have different colours, but the colours will vary depending on the type of car and the type of radio. You will need to find a manual that includes the wire colours for the different wires.
When you splice wires, you will need to strip off the coating at the front part of the wire. These wires are then made into gentle curves that are wrapped around each other. The wires are then tied firmly so that they don't come apart.