Upgrading Osram D8 to D3


Newly Enlightened
Jul 9, 2012
This upgrade is to convert my 25W D8s to 35W D3s on a Citroen DS3 sport (so only fitting I have the D3S :))

So turns out this is more complicated than I anticipated. I was praying for a direct plug-and-play, turns out it is far from that. As you can see in the pictures, while they are using an Osram globe, the ballast is Valeo branded.

Anyway, I did some continuity testing and found which two cables the two pins (on either end of the 4 slots) link to. They are earth and power signals from the car, so that is easy to splice into.

My main question is... The D3 ballast I have has 3 input points, yet I only have the two to offer. I'd assume the one I don't have an output for is for high beam, yet the D3 is not a BI-Xenon. I can't find any wiring diagrams. While there are only 2 inputs coming from my car, there are still 3 outputs going to the globe, confirmed at the globe end. Not sure what that is about.

Ignore the fact that my Ballast has 7 inputs/outputs, only the outer 2 of the 4 slots have pins.

Any help/thoughts would be appreciated.

The input and output connector from the car which supplies power and supplies the HID coming out from the ballast -https://photos.app.goo.gl/meerLMyPACg1griY8
The ballast - https://photos.app.goo.gl/xMXSDwT2uVHrjxAs9
Input and output connections on the Ballast - https://photos.app.goo.gl/sRD74JRzgzDfnkCT9
D3 ballast - https://photos.app.goo.gl/9nVj1vCJ7gRfbMT29


Flashlight Enthusiast
Feb 20, 2009
You may want to consider what damage could be caused to the projector bowl by sticking a significantly higher output HID burner in there. I would assume the usual admonishments about HID conversions apply, as there may be differences in the electrode placement which would cause changes to the beam pattern. I would suggest reaching out to someone like Daniel Stern (dastern@torque .net is his email iirc) who would able to give you some more specific advice on what the best options are for the D8s. If you do, please post what his advice is here, for others who may have similar questions.