Xenon Gas Discharge Lamps

Advantages of Xenon Light

Xenon systems provide the best light available in terms of both
quality and quantity. The optimum light distribution in all driving
situations is guaranteed by the prescribed additional systems
(cleaning systems and automatic headlight range adjustment for
ECE compliant lamps). The Xenon light is ignited and maintained
between two electrodes. A complex electronic ballast is required
for this process.

Advantages of Xenon light compared to Halogen bulbs:

• Almost three times the luminous flux (light quantity/light power).
• Significantly lower power consumption of only 35W.
• Lower thermal load on the system.
• Considerably longer service life.
• The light colour almost corresponds to daylight.

Additional regulations for Xenon low beam:

The high light power in particular is taken into account in the ECE
approval regulations. In the ECE region, headlights with Xenon low
beam may only be used in conjunction with automatic or dynamic
headlight range adjustment and a headlight cleaning system.


P/N D1R     Illumination with good low beam
D1R    Illumination with good low beam
P/N D1S     Illumination with Xenon low beam
D1S    Illumination with Xenon low beam


Bulb Comparison   HID Tips 


How they Work



Gas Discharge lamps generate light according to the physical principle of electrical discharge. Thanks to the application of an ignition voltage from the ballast (up to 30kV in 4th generation units), the gas between the lamp electrodes (filled with the inert gas Xenon and a mixture of metals and metal halides) is ionized and made to glow with the aid of a light arc.

During the controlled feeding of alternating current (at approx. 400Hz) the liquid and solid substances evaporate on account of the high temperatures. The lamp only achieves its full brightness after a few seconds when all the components have been ionized. To prevent destruction of the lamp through uncontrolled increases in current, the current is limited by a ballast.  Once the full light output has been reached, an operating voltage (not the ignition voltage) of only 85V is necessary to keep up the physical process. Luminous flux, light output, luminance and service life are significantly better than with Halogen bulbs.



 Illumination with Halogen low beam    Illumination with Xenon low beam
 Illumination with Halogen low beam    Illumination with Xenon low beam


Fault Diagnosis

Check whether the ballast is attempting to ignite the bulb after the light has been switched on. Ignition attempts can be heard clearly near the headlight. If ignition attempts are unsuccessful, the Xenon bulb should be checked by swapping it with one from the other headlight and the process tried again.

If no ignition attempt is carried out, the fuse should be checked. If the fuse is OK, check the voltage and ground supply directly at the ballast. Voltage must be at least 9 volts on 12V systems. If the voltage ground supplies and the Xenon light are all OK, a faulty ballast is causing the problem.


Colour Match HID Bulbs

As HID bulbs age, the colour temperature increases (they look ‘whiter’). When a HID bulb is replaced with a new bulb it can look ‘yellow’ compared to the original bulb. The new bulb is not faulty, and will slowly grow ‘whiter’ with use. If this is unacceptable a colour match bulb may be used (D2R-5K, D2S-5K) which is ‘whiter’ from the start, and will be a closer match to the older bulb. The bulbs are ECE compliant.


Xenon Gas Discharge (HID) conversions

Available from the internet and other suppliers are HID conversion kits which swap the Halogen bulb and replace it with a non-compliant HID bulb. This illegal and dangerous combination can cause excessive glare and leads to an enormous hazard for other road users. These conversion kits are illegal to use on public roads in New Zealand. (Refer to http://www.nzta.govt.nz and ‘Get your lights right’) HID conversion kits (an HID bulb with a high voltage power unit or ‘ballast’ which fits into the original headlamp unit in place of the original Halogen bulb with no change to the headlamp lens, reflector or housing) are illegal on any vehicle being used on New Zealand roads.