I’m having some trouble with my JM. The top left diverter isn’t holding. It’s flapping about at times like the hold is intermittent. Doesn’t happen all the time but probably 1 out of two games.
From what I can gather it’s driven from the fliptronic board. I have swapped for another known working board to see if I could isolate it to that board but problem still persists.
Where should I start looking from here?
Thanks in advance for any help.

Mech is fine. I’ve changed the coil in case of a broken wire but this hasn’t helped.
I have also swapped cpu and no change.

I have just now noticed that when the hold on the diverter is meant to be on, if I hit a switch on row 8 it starts flapping every time a switch is hit.

Thanks. Sorry I should have said I had tested all the diodes.

All sorted now. The switch on the left orbit had been getting stuck on at times hence the intermittent problem and making it hard to diagnose.
Hopefully this will help anyone else with the same problem in the future.
Very weird issue it caused and a lot of frustration trying to find.