VEMS locked in boot loader mode.

[dnb]

And nothing can seem to coax it out.
I think my car is afraid of MOTs.

The car ran perfectly on Sunday, and today it kept stalling every few minutes.  This was somewhat annoying, so I datalogged the event and the ECU was crashing for some reason into boot loader.  Usually a power cycle with the ignition key was enough to bring it out of the sulk and the car would restart.  However now the ECU is firmly stuck in the boot loader.

I am preparing my bench test spare ECU to go in the car, however I am worried about bricking it in the same way.

I'm open to suggestions.

[GintsK]

I had somewhat similar in the past. But under boost each time.
That time I tried to change Atmega - same issue. After changing the whole board everything was solved. Now I think about some dead capacitor in Atmega supply circuits. No way to brick it on bench tests.
It starts with wrongly installed NOS solenoids with terrible flyback spike in VEMS supply.

[Ignitec]

I had one locked in boot mode. Changed atmega, and everything was fine...