To elaborate, Fiat eLearn for the x244 model, on which my attachment in post #2 is based contains wiring diagrams, but it does suffer from some errors and emissions. It is available in the downloads section at the top of the page, and runs on a Windows computer. Some of that version of eLearn is available online
here. Some of the diagrams from 4cardata are unreadable, and at least one description is chopped.
One thing to note is the need for F24 in the LH cab fusebox to be OK. Not shown on basic dipped beam diagram (annotations are mine). This need for F24, has previously caused problems for forum members.
I will now attach copies of my connection table for the"Switch Control Panel", H090, and layout of Fusebox B002, (LH cab).
To help others please report on resolution of fault.