200 HPDI only runs on 4 cylinders in gear

I have a problem with one of my 200 HPDI motors. The motor only runs on 4 cylinders both in neutral and in gear.

The obvious thing is the neutral safety switch, but it is working correctly, or least as far as YDS is concerned. It shows ON when in neutral and OFF when in gear. Cylinders 2 and 3 show as off in neutral and in gear, and it is definitely only running on 4 cylinders.

Any ideas on what this could be or where I should look?

I understand that there is a second switch, a shift interrupt switch, but don't know where it is? Where is this located and how do I test it?

Thanks

Re: 200 HPDI only runs on 4 cylinders in gear

Update: Figured out the second switch in the remote control is nothing to do with running on 4 or 6 cylinders.

Did find some damaged wires going to the oil transfer on the boat. Repaired these and cannot get the problem to repeat.

Here's what I do know:

1. It did show a code 13 error for the neutral safety switch.

2. The neutral safety switch tests good and shows in YDS as doing what it is supposed to, ON in neutral and OFF in gear.

3. The motor was in what appeared to be RPM reduction mode, only 4 cylinders and not much more than 2k RPM.

4. The problem was intermittent.

5. The switch does not appear to be faulty or the cause of the issue, despite the code 13.

6. The alarm buzzer does work, but does not sound when the fault occurs.

It may be wishful thinking, but I have to wonder if the damaged wires (blue and brown) going to the on-board oil res didn't somehow trigger RPM reduction mode. Why this showed up as code 13 and sounded no alarm is a mystery to me, but sometimes Yamaha wiring is more complex than I may first think.

???