Right background to this is the fact I fitted genuine VX Xenons to my pre facelift Vectra C.
When I fitted them they did not work and flashed/pulsed and turned off.
I investigated further and found that by turning Xenons on in the UECU (Underbonnet ECU) solved all my issues.
Now this is the reason it worked:
Standard Halogen bulbs need a pulsed supply to make them last longer. Xenons will not work with a pulsed supply which is why aftermarket kits come with capacitors to stop the pulsing. They also come with resistors to stop the bulb out warning coming on as well. If you enable the Xenons in the UECU there is no need for capacitors or resistors.
So if you get Xenons enabled you should be able to fit a standard Xenon kit which is much cheaper.
You can get the Xenons enabled before you fit the kit as it will have little short term effect on the original halogens.
This should solve all the fitting issues with HID's. Also the orginal headights are rated for fitting Xenons as there is no difference in the headlight construction between Standard and Xenon factory fit. The lenses are the same.
I have mentioned this today to HIDs Direct who are going to put it on there website and offer a cheaper kit.
Although I know the above to be true I think we need a couple of members to try this to make sure/confirm it works as I think I might be the only one to have done this conversion.
The information I gained while fitting the Xenons is not all my doing as several other members helped so I cannot take the credit for this if it works for everyone.
Please note the above info only applies to prefacelift full canbus cars as I am unable to confirm this for half canbus and facelift. There are more issues on fitting Orginal VX Xenons to Facelift cars than prefacelift and I am currently working on a solution with another member (Lump) which although drawn out may have an end fix.