During this cold weather I have noticed that with the Start/Stop active the heater fan soon blows cold at rest when the engine cuts.

Is there a software mod. which would disable the heater fan when this occurs and restart the fan once back in motion??

I find myself turning the blower off and on during stop/starts.

I know this also depends on other factors like the demist function but in the manual it says it will not operate if............

› The difference between the outdoor- and the set temperature in the interior is not too great.

but I suspect this only applies if the A/C is on ???

It's because when the engine stops you are not circulating hot water via the water pump through the heater matrix. Easiest option is turn stop/start off when colder weather. Fuel economy saving will be negligible in cold weather anyway.