Neff W5420X0GB/18

Neff washing machine with fault code. start/pause light flashing, 800 AND 400 spin lights flashing, ready light flashing too, beep beep noise. Symptoms basically no go! Now this machine has had a history of the door not opening before but never screwed up when I had a look, it seems now it has decided to muck up. Got a feeling in my water that it is the door lock even though the thing locks but there is no clicky click noise from I/lock so could be the feed to the lock via pcb or lock itself. I have tested for earth leakage the motor, motor brushes ok, pressure switch, heater, tried the old Bosch reset trick to no avail, tried the Siemens other rest trick to no avail there either ( did not expect success but grasping at straws! ) There is a brick red small pcb attached to the rear top X member of the chassis, any idea what that is, any relevance? Does anyone know if the fault code as I describe point to i/lock switch please ot elsewhere. Thx.