An external car antenna can be broken from a mishap during daily driving, a minor accident or even as a result of malicious behaviour. You can fix a broken car antenna yourself, saving the cost of an expensive session with a car repair or dealership. A replacement car antenna rod of the same colour as the broken one will be needed, along with a few supplies from an aftermarket car supply.
Park the car outside in an area with plenty of overhead sunlight and out of the shade. Place the emergency brake on for added safety. Pop the boot open.
Wrap strips of paint masking tape around the base of the car's antenna to protect the paint on the car body.
Unscrew the screws holding the antenna's base to the car's body from the underside of the boot with the hex wrench.
Carefully pull the rubber base up and off the broken antenna. Pull the antenna off the body of the car.
Loosen the screws on the base of the antenna with a Phillips jeweller's screwdriver. Remove the wires attached to the screws.
Attach the wires to the loosened screws of the replacement antenna. Tighten the screws.
Place the replacement antenna into position where the original antenna was located. Screw the replacement antenna into position with the hex wrench.
Place the rubber base over the replacement antenna. Push the rubber base down onto the body of the car. Close the boot.
Slowly remove the paint masking tape from the car's body. Clean any tape reside off of the car's body using circular motions with a microfiber cloth.
Disconnecting the car's battery can help prevent any chance of an electrical problem when working on the antenna--but should only be done by someone who has experience in the proper method of disconnecting a car battery.