Sorry I have ZERO M3W experience and have no definite answer to your issue, though it would seem to me that your process of overcoming the fault may be similar to re-booting a PC, though in this case you are performing a similar action on the ECU...?
Given the many variables in such situations in a digital Morgan, without access to the logic of the operation as written into the ECU chances are that anyone might come up with a considerable number of theories relative to your issues...? Were my Morgan digital, I would consider having access to fault code readout the most important item to have beyond the ign key, and as such it should ideally be available on my mobile phone...?
Your process of re-booting the ECU on the move causes concerns assuming there is a steering lock built into the ignition lock..? Be safe.. and I hope you resolve your issue soonest..
