Hotpoint WF340PB lights flashing

I went to this WF340 10 days ago – original fault was it didn’t turn on, yet all the lights flashed.

I cleaned up the carbon deposits from around the motor brushes and got the insulation back up from less than 4 MegOhms to over 1000 MegOhms.
Insulation was otherwise OK on all components.
Checked out the module at the same time – it had evidence of overheating (soot, in other words), but not in the areas highlighted by EMW’s help sheet, so I thought I’d run it to see if we’d got away with it.

It worked OK and then continued to do so for another 3 or 4 days, then stopped again.

Ordered a replacement module from EMW, which I fitted this morning, and on functioning it, although it seems to fill ok, agitate ok, drain ok and spin ok, I get occasional flashing of the 3rd or 4th , or sometimes both, lights, yet the on/off light is not flashing, so I believe it’s not an error code.
She then tells me it was also doing that for a few weeks before she called me out.

It also seems to choose when to let the machine’s on/off button work, either to switch it off, or to switch it back on if you’re lucky enough to have switched it off.

I’ve checked the input board for signs of damage – none.
I’ve checked and tightened both end connectors joining the input board to the module.

Then I noticed that the 3rd light (Rinse Hold), or sometimes the 4th light (Mini Load), flashed for around 10 seconds whilst the machine was switched on, but the door was still open, not having selected any program at all.

I took the replacement module off and brought them both home, for further investigation and to prevent her from knackering a replacement module unnecessarily.

Any suggestions, please?
Thanks,
Pigpen.