Even though a common name for most HID lights is “Xenon headlamps”, that contain Xenon gas, which is used to allow the lamp to produce a minimal amount of light immediately after powered-up, in order to accelerate the (much longer) run-up time of the lamp. It has a distinctive bluish color which separates HID headlamps from the regular lamps with tungsten filaments or other halogen lamps. Even though they give a greater amount of light output per amount of electricity power input, HID lights are still mostly used in low-beam operations and very rarely on high-beam lamps. Mostly all vehicles brands are now providing these HID headlamps as a standard equipment not only in luxury cars but also on trucks, Lorries etc. However, these xenon headlamps can be retrofitted to the vehicles where it does not come as a factory-fitted component.

The main advantage of HID headlamps is the increased safety provided to the driver and others on the road by the more usable light compared to the regular Halogen ones. Also, the luminous efficacy, the reduced power consumption and the longevity (the average service life of a HID lamp is approximately 2000 hours, while a Halogen lamp has between 450 and 1000 hours of functioning) are some of the well-known benefits of HID xenon lamps.

Scania Headlamp Fault Main Headlamp Warning Message

Although Xenon Lamp lifespan is much larger than halogen bulbs, they do eventually fail and many vehicles equipped with these bulbs are now requiring replacements. This is very common for an electronic component to fail due to life completion or being damaged due to moisture or dust contamination.

Your dashboard displays a warning message “headlamp fault main headlamp” when there is a fault in HID lighting system whether is control unit/ ballast or a bulb. Flickering or failed lights can be caused by several other components within the HID lighting system and it is usually difficult to decide which component is at fault, bulb or ballast or simply the loose wires causing this problem.

D1R D1S 12V 24V HID bulbs are fitted on many different Scania HGV Lorry ar trucks Scania R series R310 R420 R440 R450 R480 R490 R500 R580 R650.

Diagnosis of Bulb Failure

However, before replacing the D1R 35W Gas Discharge Xenon HID Lamp, it is important to rule out other factors that may be causing the lighting issues.

The most commonly used bulb on Scania is 1900397 D1R 35W Pk32d-3 or Osram Original Xenarc 66150 66154 66052 66152 66156 D1R bulbs.

In addition you can fit Philips D1R XenStart bulbs with the following part numbers 9285168294S 9285141294 9285140294 8897814 9285108294 85409C1 9285142294.

Usually when the bulb fails, the centre of the bulb gas becomes dark showing it has rotten but it may not always be dark so it is best to first change the side of the suspected bulb to ensure if it is really bulb and not the ballast failure.  

Having working headlamps is necessary to keep your vehicle legitimate on the road as well as to ensure the safety of driver and others on the road. These HID lights are an added safety feature and they must always be in working condition to avoid any penalty by not abiding the laws.

Fix the Faulty Component

When you are able to identify the real faulty component which in this warning message case is a D1R D1S 35W 24V HID bulb, then replacing the old bulb with a new one will fix this issue.

Although, this replacement is easy and can be done by yourself but taking it to a professional dealer is advisable to get you the right specification component and saving you time and energy for replacement. Also, sometime replacement may require coding so it is better that you consult a mechanic for replacement and coding afterwards.