I'm thinking to build a small plug-and-play system that measures humidity in the light and then power a 12v air pump to move the air within the light.
The controller will be programmed to only operate when the supply voltage is above a certain value. Therefore not being responsible for draining any cars left disconnect from trickle chargers.
It will slot in the top circular plug position (clear on pre-facelift, black with side vent on facelift), as I've made plugs for here anyway so I would just need a hole for the wiring. For UK models, I would move air through a vent port, but that would need different programming, as to move some air first before taking a measurement. As the sensor would have to be located externally. Though not a major issue just some basic plumbing and coding.
I'd like to help someone who has fogging, as this would be the ideal first case. During my days refurbing headlights, I was never able to solve the cause, a new seal or sealant around every joint didn't seem to fix some old lights. Occurrences of one light being an issue from a pair, full clean, reseal, tyre shine all the rubbers and STILL the same light. I'd like to finally solve this issue,
If anyone wants to be the guinea pig, it would be great.
Thanks