Found this comment on another forum for the Mazda 3; perhaps a forum with less geriatric (and crotchety -self included) users than this one.
"Tristan-cx5 said:
@Baldo Mero : Make a backup before changing anything.
Your new values for the test of disabled i-Stop:
731-01-01 5020 C824 21B7
731-01-02 080D 1926 901F
Please let us know, if it was successful or not.
Actually it was.... No problem, system off. I would be happier if instead of a permanent off it would be possible to get an off by default and turn on with the dash button. But anyway, I can confirm that the address is the same in 2019 mx-5"
Which, beside appearing to be gobbledegook, means deep inside the firmware controlling the car are codes that switch i-Stop off. Dealers, worthy of the name, can do it.
Taken from
https://www.mazda3revolution.com/thread ... 3/page-238
But on a manual CX-3 I don't find i-Stop to be a problem in any way whatsoever. I
ts real function isn't to save you money but to save 1500 litres of exhaust gases being pumped into the atmosphere every minute the car sits in neutral with the engine running.