You're spot on for this one Techno_nz. It was a broken wire in mast cable.
I managed to use one "not-used" wire so it works now but the customer should get new cable of the warranty. The machine is only three months old and has 26 hours.
Overall, I'm not sure that I like how WAV60 wiring is built and routed.
Somehow it looks like a step back from WAV50 to me.
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