Fakro rooflight problem

[Adam2]

So after 4 years my rooflight seems to have stopped working it's FAKRO DEF-D U6 10K 100x150 so that's 1m x 1.5m electric opening that has integration to ZWave for home automation.

 

Symptom is that the green light adjacent to "P" button on the window is always on and the other button (should be a manual up/down button) ) has a light which will briefly flash once if pressed long enough.

 

Does anyone have any suggestions for troubleshooting beyond what I have done so far: power cycle, random presses on the 2 buttons???

 

I did call re support and the cost, please sit down, is £300 + VAT for a call-out charge plus the cost of anything they need to fix it. So I guess you can see why I'd like to explore this if poss before starting down that line but expect it is likely the eventual outcome.....