i started to use my auto heater now because its getting cold and im not sure when to have it turn on. i usually set it to turn on 15 minutes before i go to my car but it seems like it really doesnt make a difference with the temperature inside the car. how soon do you set yours to???

 

Auto Heater? Are you talking about the vent?

 

Yea the setting in idrive that allows you set a timer let the heater turn in the car.

 

Are you talking about parked car operation?

 

There are two possible options.

1) uses the residual heat. So if the car is parked for a long time it won't help. This is helpful if you leave someone in the car and don't want to let the car run but still wish to keep the passengers warm. Example, leave someone in the car while you run inside the store to pick up something quick.
2) vents out excess heat form the car. Helpful if you part outside at work on a hot sunny day and want to vent some of the hot air just as you leave work.

 

I could never figure out how to activate it.

 

Im pretty sure it isnt a heater just air conditioning you can set to work on a timer.

 

yup thats it..

 

As explained above, parked car operation doesn't provide any heat, just ventilation. The car can't warm itself without extra equipment, etc. (do a search on the term: Webasto). In the US, there is no BMW factory option that allows the car to pre-warm itself, only ventilate the cabin to try to cool it down on hot days.

The REST function, often referred to as "residual heat" function is helpful if the car is already warm and you're going to leave it for a short time. Using this feature allows you to return to a warm car if you're not gone too long...

 

I don't thnk it vents any air OUT of the car...it simply turns ON the fan operation...which is gonna just circulate the air inside the cabin. I hope I wrong, because it would be REALLY nice if it would suck the hot air out of the car, but I think it just circulates the air.