I read this with optimism and was hoping I would be able to send you a bottle of your favourite tipple.
Sadly, it didn’t work.
Thanks very much for your research and efforts in helping.
The only other thing I can think of is to use FORSCAN software and an ELM327 usb obd cable.
This is how I programmed extra keys in to my ECU.
You get a 1 month advanced licence trial when you load the FORSCAN software so the only cost would be the cable. ( Mine was less than £20 )
The only snag at present is my OBD 2 reader wouldn’t connect.
The chaps quite sofisticated one wouldn’t either.
I think therefore I am currently in the hands of Mazda.
In fairness, he was extremely helpful and gave me some quite reasonable prices.
He was going to do a full diagnostic check first before anything anyway.
Time will tell and fingers crossed they can sort it.
This thread seems to indicate that the obd port is only live when the “room fuse” is good and there is 12v to it.
His issue seemed to be the main 120a fuse.
I would make sure the room fuse has 12v to it and take a look at the main 120a fuse
I never mess with wiring / electrical as never feel competent enough and when it goes wrong ball ache hopefully you find solutions Richy TDA