CECO Fadec!
There are some possible loops or holes in the logic. From memory (which can't be trusted these days) it is not possible or legal for that matter to start this engine in MANUAL. This can come about in a couple of ways. Collective switch set to manual or the engine has been shut down using the OVSP TEST (which is normal) and the throttle has not been returned to OFF from the previous shutdown. In this case the "levers in the HMU reset as the fuel pressure bleeds off." There would be an ECU degraded annunciation and theoretically the engine should not start. To rectify the problem the throttle needs to be placed in OFF and the engine motored to give enough pressure to reset the levers. Make sure your battery is good if this happens in a remote area!
Another catch is because the key position is not visible from the pilot's seat and you go through all the start procedure and omit the key, you push the starter button and nothing happens. Oh hang on, the key. When the key is turned ON the engine will immediately begin to start. Can be a bit disconcerting and leave you feeling left out of the control loop.
If your battery is a little weak the FADEC can shut itself down mid start and the engine will stop right where it is and look at you and stop accelerating. It can take time to notice - pay attention!
If the PLA (Power Lever Angle) potentiometer is goosed the engine can decide to accelerate on it's own from idle. This is a rare occurrence and has been rectified with luck. Didn't help in the middle of BF Indonesia though.
Another area that may be an issue, is if you have pilots with previous MD experience, that switch on the collective that is in the same place as the old N2 trim is most definitely NOT the N2 trim switch!
There was also an issue with quality control and incorrectly sized sockets installed in the FADEC control relays.
The one upside of the FADEC is it has increased the TBO and Hot inspection times on what is really only what the C30 should have been in the first place.
Remember the 600N was NOT designed it just growed like TOPSY. There never was a market for this aircraft and it would appear that's still true.
A new tailboom is over USD 100G.
Have moved on now to United Technologies equipment, P&W C with Hamilton Standard FADEC. Totally benign and you can start it manually. A few small problems with dirty connectors which comes from them being loose, but that is common to all.