Headlight: common defects and their signs

1. Bulb blowing out, as evidenced by the headlight not turning on.
2. Defects of wiring.
   • One or two headlights fail to turn on.
   • Headlights got dimmer.
   • Headlights fail to turn off after the cabin switch is in the corresponding position.
3. Housing depressurisation.
   • Condensate forming inside of the headlight body.
   • Light is dimmer, soiling is seen in the headlight.

How to repair or replace headlight?

Repair of the car headlight can include its cleaning and restoring housing hermeticity. You can also clean up oxidised contacts. But before this you should make sure that they, and not a blown fuse or relay, are the cause of the problem.

If the bulb is blown, it should be replaced. For this you should remove the protective cap from the reverse side of the headlight and disconnect the terminal block from the bulb socket. Access to the bulb can be gained through the bonnet or the arch wheel depending on car model. Once wires are disconnected you should unscrew the defective bulb holding its cap and then install a new component. Remember that you shouldn’t touch the halogen bulb with bare hands because grease and dirt on the envelope will significantly reduce its lifetime.

In some cases such as mechanical damages on housing, broken electrical connections or fasteners, faulty reflectors, you should replace the headlight in assembly. For this you should do the following:

1. Demount headlight fasteners, remove the electrical connector with the help of special tool, push up fixations
2. Remove headlight body fixations and demount the broken component.
3. Install a new component and assemble everything in reverse order.
4. Perform regulation of optical beam.

When replacing the component, it is recommended to buy a headlight kit and install new devices on both sides because different headlights can be of different intensity and have different optical beam direction which can negatively affect driving quality.

Turn car ignition off before starting servicing.
Disconnect the wire from the battery negative terminal.
The bulb can be touched in clean gloves only, as oily stains on its envelope will cause its darkening during heating.

Types:

1. By housing material:
   • metal;
   • polymer.
2. By light source:
   • with incandescent lamps;
   • with xenon lamps;
   • with LEDs.
3. By mounting side:
   • left;
   • right.
4. By driving side:
   • for left-hand traffic;
   • for right-hand traffic.
5. By reflector type:
   • with a parabolic reflector;
   • with a free-form reflector;
   • with an elliptical reflector.