The decision to go there always is Chas...
They take time to warm up for one, and I'm still confused as to why the dip come bright after 8-10 seconds and that mains take so much longer.
Second issue may be something to do with US regs (maybe) but the dip and main units are treated together in the wiring. Imagine the OEM H4 plug that goes onto the twin filament bulb, well the back of an H4 bulb looks something like this chappie...
Not too apparent from the photo, but of the three wires, one wire goes to the dip beam module single filament H1 bulb and the other goes to the main beam single filament H1 bulb.
That means, on dipped beam, only the dip is on (just like OEM), but when you switch to main beam, only the main beam module is on (unlike OEM). OEM on main beam (on mine anyway), has the main beam filament of the dip/main plus the single main beam module next to it. 4 main beams in total.
... Does that make sense to you...?
So to replicate the OEM set-up, the main beam module has to power a separate (added) relay that re-energises the dip beam module.
The result will be (when I've figured it out) when on main beam, both dipped and main modules working together.
That's why I want a light bar too, to compensate for losing the main beam from the single filament dip beam module.
Oh, my head hurts!
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