A simple headlight question! The headlight wiring on my car has been messed about with around the plugs going into the headlight (wires soldered together and taped up). My question is, when you turn on the headlights and select dip beam does this just switch on the beam in the light with the twin filament bulb? Then when you turn to main beam, does this illuminate the main beam (of the twin filament bulb) and the additional headlight with the single filament bulb? I know this sounds a bit thick, but is that how they work?. Mine does not switch on the single filament light on main beam, just the one in the twin filament setup.

Now a bit more of a technical question. The wires into the back of the headlight plugs have a ground pin, a sidelight pin and 3 others. These 3 others have 1 yellow and 2 white wires attached. I have sussed that the yellow wire is the dip beam. Of the two white wires, only one powers up on main beam. Should both power up? Are there any connecting plugs in these circuits and if so where? Also, is one headlight wired up (which one) and then fed across to the other or are they both independently wired?

Finally, where is the relay for the in bumper spotlights?
Cheers in anticipation of someone humouring me.