Start with set the controls to control rear seat from the front then use common sense to get even air flow.

It's entirely impossible to cool a car to 60f off its hot outside.

Start with all controls on auto, make sure the vent control mix for the front seat is a couple spots into the cold passenger and driver then hit auto so fan speed is automatic.

Press auto repeatedly until intensity says medium.

Set temp everywhere to 74F (23c) and wait to stabilize when the fav speed drops to where you can barely hear it. Then you can slowly go lower or change the vent mix a little cooler.

I find the side vents a little week in our '12 50i, so I closed the center dash vents to get a little more even cooling in the front seat.

Once you get the front under control with front control of the back seat then do some back seat testing: set that to auto and 74F also and see if you can get it to self regulate.

I see this sort of thing all the time. "max Ac" is meant to run for 5 minutes. Also, never sure why people fight with manual fan control when a car has auto climate. Set it forget it.

If you can't get front to work properly with this testing method the blower or blower unit (FSU) isn't working properly (or something like evaporator not cold enough).

Start with the test method described and post feedback.

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2011 E70 • N55 (me)
2012 E70 • N63 (wife)