High Intensity Discharge (HID) lights are a popular choice for car headlights. These bulbs produce a bright light that is perfect for nighttime vision. HID bulbs are connected to ballasts that control the voltage and current frequency to ensure that the bulb gets the right amount power. If you are installing an HID ballast and bulb to your car, test the units first to make sure there are no problems.
Open the bonnet of your car.
Put on latex gloves. Oil from your fingers can damage the HID bulb and reduce its lifespan.
Connect the HID bulb to the ballast by plugging the ballast plug into the bulb socket.
Use two wires to connect the ballast to the car battery. Ballasts made for cars usually come with a plug that encloses the positive and negative wires together. Attach one end of the first wire to the positive terminal on the battery and connect the other end to the positive terminal inside the ballast plug.
Attach the second wire from the negative terminal on your car battery to the negative terminal inside the ballast plug. If the bulb and ballast are working correctly, the bulb will light up.