Yes, that's what I meant. So I unplugged connector 1, connected the multimeter to black/white and lightgreen on the unplugged connector on the bike side, ignition on and then the indicator to the right on. And repeated for left hand indicator. In both cases I got a voltage that was going up and down (I.e. lights were supposed to blink).
With the left side indicators (good side), the front left light was not working (because connector unplugged) and rear left was blinking at double speed (what you expect with 1 light 'broken').
When doing this on the right side, none of them are working still.
Does that mean it's probably not the yellow connector (because that one is responsible for the power of the whole indicator system, both front and back), and it needs to be checked on the rear connector? (I read there is one supposed to be under the seat in the back?)