Hi everybody.
Thanks for reading.
Today i had a bad day at the office!
I have E92 335i - MSD 80 - N54 in the workshop with internally faulty DME (internal injector issue but unusually this is not faulty mosfets).
The car runs on three cylinders with original DME.
I managed to find a replacement DME from a 135i - N54. This one is the upgraded MSD81.
When the time came to swap the DME i made two fatal errors!
1. I failed to take a backup of the donor MSD81 before starting (Lets just say this is a mistake i will never make again!)
2. I tried to direct clone the original MSD80 to the donor MSD81 instead of changing ISN / programming / reset working hours.
So the process appeared to go well but after cloning i tried to do backup of MSD81 and realised things had not gone to plan.

When i try to unlock the MSD81 DME i get an error saying 'çannot identify ECU'. If i ignore and continue, i can read flash/EEprom. If the MSD81 is connected to the car I get Fan and coolant pump running full speed. I did not try to start the car but I'm very sure the car would not start. I can still communicate to the MSD81 via OBD but MSD81 identifies itself as MSD80.
I read ISN from MSD81 and ISN has been changed to match the original MSD80.
Hexprog support tried to help / were helpful but basically told me i turned my MSD81 into a paperweight because i failed to take backup of donor. (as i said before, this is on me. Stupid mistake).
Support are probably correct but i wanted to check. Does anybody have other suggestion how to resurrect the MSD81 ?
I would be very grateful. Finding another suitable DME is going to be difficult !