High beam headlight filament bulb: common defects and their signs

1. Burning-out of the tungsten filament
   • The component stops reacting to turning on from the cabin.
   • The bulb envelope is darkened on the inner side.
   • The trip-computer gives the component failure signal.
2. Violation of contact in the holder
   • The bulb is not lit at light turning on.
   • Lamp light becomes dim.
   • The lamp blinks, for example, during obstacles overrunning.

How to replace high beam headlight filament bulb?

Take into account that in some cases, the cause of light absence of the headlights is not bulb failure, but burning-out of a fuse. If bulbs of the marker lights, bulbs of stop signals and light bulb of the turn indicator burned-out together with the high beam headlight bulbs, than the cause lies in the fuse.

If the defect cause lies in poor contact of the bulb holder and the bulb, you need to remove the component and clean oxidized contacts. Also, squeezing of the bulb holder walls may help in case of non-tight adherence of the bulb to them.

If diagnostics showed defectiveness of the bulb itself, it should be replaced. As a rule, a standard filament bulb has lifetime limit of 500 – 1000 hours, a halogen one is more durable, its lifetime limit is 2000 – 4000 hours. Sometimes the part may break down earlier, then it should be replaced.

The replacement process is quite simple and it includes a few easy actions:

1. Remove the rubber cap from the headlight body in order to gain access to the bulb holder.
2. Disconnect wire connector from the bulb outlet.
3. Unbend retainer clip, which retains the component and pull it aside.
4. Remove the defective part.
5. Install a new part. Remember, that it is prohibited to hold a halogen bulb with bare hands. Otherwise, oily stains will be left on the bulb envelope, which leads to local temperature increase of the bulb envelope and premature breakdown of the component.
6. Connect the wire connector and close the protective cap.
7. Perform adjustment of headlights inclining.

It is recommended to perform bulbs replacement simultaneously on both car sides, because otherwise headlights beams will have different intensity and color temperature, thus worsening car handling comfort. If there is no such opportunity, try to prefer component of the same manufacturer, as of the component installed in the other headlight.

Remember, that replacement process for the cars of various models will have some differences. For example, in some cars, you need to remove the battery in order to gain access to the component, and in others, replacement is performed through the wheel arch. That is why, apply to your car technical documentation to obtain comprehensive information.

Turn ignition off before starting servicing works.
Disconnect the wire from the battery negative terminal.
It is necessary to use clean gloves touching the bulbs, as greasy stains on the envelope cause its darkening at heating.

Types and average operational lifetime:

1. By envelope content:
   • halogen – 2000-4000 lighting hours;
   • vacuum – about 1000 hours.
2. By cap type:
   • flange;
   • bayonet;
   • tubular;
   • capless;
   • with plastic cap.
3. By quantity of glowing filaments:
   • single-filament;
   • double-filament.