Problem solved !
You go in visualsettings.dat in update/update.rpf/common/data, then you need to find "emissive bits".
And there you change the values for the following lines :

car.defaultlight.day.emissive.on "190" car.defaultlight.night.emissive.on "40" car.defaultlight.day.emissive.off "0.01" car.defaultlight.night.emissive.off "0.01"

and you get this :