Second sebo x4 has a problem with the automatic head adjustment not going up and down and also when upright constantly flashing the stationary warning light even if i pick the vac up. I have tried changing the servo motor, pcb and brushroll but still showing same fault. Could it possibly be the brushroll sensor that has gone?
We had one recently that did as you said, and eventually we found that in the area near the PCB on the side, there is a little circular magnet that is needed to work the height sensor that had come out. We removed the side PCB and it was stuck under it. Found where it had come from, glued it back in and presto.
Brushroll sensor is possible but unlikely; based on the fact we change so few.
The handle is harder to say without seeing it. I have seen the odd older one with a carefully placed self tapping screw, pre-drilled and screwed in. Probably for the same reason. But one must be cautious if doing that as the wires run through it as you know.
Anyone who has any other ideas, please do chime in.