Interesting observation with max heat and the hybrid system
 

It was a little cool this morning and I thought it was a good opportunity to fire up the heat on the HVAC system to burn off any dust etc from the heating element as a result of lack of use over the summer months.

I opened up the sunroof and cranked the heat up to MAX. What surprised me was that I couldn't get the car to go into EV when the temp setting was at MAX. When I was at a street light stopped for example, the ICE would run but if I turned the temperature down by only one degree from MAX, the ICE would shut off and go into EV.

I assume then that maximum heat draws a significant amount of power which requires the ICE to run? If so, I don't see the value in ever using MAX on a very cold day but rather set it one degree less in conjunction with the heated steering wheel and seats...

That is correct! Heavy use of the climate control, will not allow the auto start/stop system activate.

This is from the OM:

https://cimg1.ibsrv.net/gimg/acurazi...714424f97c.png

Thanks for the explanation! In theory the logic makes sense - if the climate control system is in heavy use, the auto stop might not activate. But the system logic just seems so linear to disengage at MAX but operate as expected with only one degree variance. I can't imagine the system load is that severely different between MAX and one degree less.

But thanks for the OM explanation - I really should read that thing sometime :)

You are too funny :)

Most cars that have the conventional auto start/stop system, deactivate it when the climate control is set to MAX COOL-MAX HEAT.

My brother in law just leased a Guilia, and that is in the owners manual also.

I think they just do it to be on the safe side......

max heat needs engine heat - I do not believe it is a heat pump. Max cool would require more electrical power