Technical No dip beam, help please! Mot due in a week!

[Hisnibs]

I posted last week I was having issues with electric windows and dip beams. I have resolved the window, it was a faulty switch.
The lack of dip beams has me baffled. I've replaced the light switch stalk, checked the fuses and tested most of the 21 relays!!!! I still can't get the dip beam to work, main beam and side lights work. Bulbs are all good. I've wiggled all the connecting plugs behind the dash, by disconnecting and replacing them.
Someone please tell me there is a simple fix????? Thanks

 

[Communicator]

For continuity I have copied this post into the original thread, and posted a detailed reply.

 

[Largeround]

I have a 2004 1.9 motorhome and I've had no end of random electrical faults. I've been chasing a dipped beam fault, where the lights don't come on then "some time "later suddenly burst into life for 3 years now. It is worse when it is damp or raining and driving me mad. I don't think the schematics I have will match what has been shared already. I know it is a simple fix but just can't track it down as once they start working, they stay on and no amount of kicking will re-create the fault, which you would expect from a dodgy joint etc. I even dismantled the fuse/relay board last week, that's a hot bed of potential bad joints! but I did not resolve my issue. Interesting to see the module behind the dash is involved? I am at the point of just fitting a new relay etc and wiring accordingly. So frustrating!!!