To report on progress, and more questions.
I have not yet found the problem. I found three relays behind the dash. All worked OK.
I have a wiring diagram that seems to be fairly accurate.
According to that I should have 12V on a purple/red wire at the hazard switch. That is OK.
I have tried to mannually short the wires at the indicator stalk. No change.
I can not find any faulty fuse. Yet.
Questions.
According to the wiring diagram there should be something called a "Flasher unit". How does such a thing look like?
Since the hazard switch has 12V, but I dont hear any relay click, I start to wonder if the problem could be in the earthing side of the realys. What do you think about that idea?
Best regards