Try fuse F6 30A in the engine box, it supplies the power wash relay RLY14 in the same box.

 

by engine box is there one under the bonnet or the one in the footwell?

 

And don’t forget to switch the headlights on first.

 

So…. The arms are now working they go in and out but no water is coming out does this mean the nozzles could be blocked? If they’re driven by pressure

 

Definitely.

 

What are the requirements it has to meet in order to wash the headlights?
I know it’s 4 times but is there a specific time you have to wait in between?

 

Answering my own question here…..
I figured it out finally…
So they won’t activate again if pushed within 10 minutes however if pushed 4 times and time taken is let’s say 30 minutes they will activate.
this will reset itself if you switch the headlights off then back on again. It’s all working now flushed the system out completely and they’re working perfectly!
Thanks for the help!

 

Excellent news and thanks for the update.