Hi all - I live in Portugal and I'm new here

After 1 month at the garage the mechanic (he is good) still cannot get the engine started:

History.
1. Car just stopped running, one second to next - like pulling out ignition key.
2. Mechanic has used 3 different diagnosis units on the car with no luck getting into ecu.
3. Last week an English mechanic visited my mechanic with a different diagnosis unit and couldn't read the ecu - even though my model was listed on his device.
4. I have been told thet PROBABLY the ecu has died.
5. I am just about to organise the ecu to be sent to England to be tested and if neccesary, repaired at Turner Diagnostics (who have an excellent reputation). I cannot find any service like this in Portugal.

So, 6 - is there anything to check before removing the ecu and sending off - my mechanic has been all over the car the "old fashioned" way and is at the end of his tether (not the only one!). Anything less obvious to check?

Thanks for helping me get my only vehicle back on the road

Simon