Suzuki Club UK

I need help!
Have full beam fine, no dipped. Checked and replaced fuse (old one was fine anyway), bulbs are surely fine as I looked at filaments with mag glass, got a circuit across terminals for both filaments plus the odds of both failing must be slim.
So, off a meter I have all 3 connectors in supply side (socket from loom) giving earth when lights all off.
When on main beam I have 12v on left pin (as viewed with centre pin at top). No 12v anywhere when switch on dipped.
I have a Haynes wiring diagram but it is impossible for me to follow. I'm no expert on sparks and this has me baffled.
Any help much appreciated.

This is the wiring for the Japanese built models. IE switched earth type.

Thanks Darrell - mine's Spanish but they may be the same? From above i still don't understand every terminal being earth when off - wondering what that bar thing with 'blank' under it is. Told you I was no sparkie

As with all headlight issues. Unplug Spanish running light resistor in passenger foot well. If it fixes it put it in the bin

When checking at the bulb connection for power/earth remember to also disconnect the other headlight. The other bulb filaments will also allow power/earth through to the meter and give confusing results.

This is my take of the Spanish wiring (Normally switched live).
Don't hesitate (anybody) to comment if you see I've screwed up.
I can't guarantee all the wire colours are correct as I can't read them for sure

Thanks for help. So I need to find this running resistor and try with it disconnected. Wonder what it does and is it a part of lighting cct as I don't see a resistor anywhere in diags above.
Good point re disconnect the other light, that will explain the earth everywhere I expect.
In the end though, if it isn't bulb or fuse and wiring has not been messed with (not by me and looks undisturbed) do I need to get into the stalk switch - looking for a physical/mech fault?

I think Dan is referring to the dip-dim unit fitted to some models. This is in the passenger footwell, but when it screws up the headlights stay on, although dim.
I would check for power out of switch as close to the switch as possible first.
If none I guess the switch is going to be stripped