don't know much about this model but water mite have got into the dash, if you go ahead and open the dash there's a chance electrical pins 11,21 and 31 will have corrosion as they sit right down low inside the dash, these need to be good for the lighting circuit, btw the dash controls the headlamp relay and only completes the circuit when the engine revs over 1500rpm.
chris p duck
March 2021