# manual to auto climate control



## andy_thomas (Oct 7, 2002)

Further to the recent and not-so-recent threads about auto climate control vs manual air con, I did some testing with a spare unit I managed to get my hands on.

The main difference between the two is how the high (demist), mid (face) and low (feet) level flaps are controlled. The manual (rotary-dial) air con control panel allows only two flaps to be open (and then only partly) at any one time. The climate control panel can select all three. While the manual unit is limited in this respect it can at least vary the bias between each two sets of flaps (high-mid, mid-low and low-high). The auto unit may do this too, under fully automatic operation, but it is not selectable by the driver.

The manaul unit requires only one (or possibly) two motors to achieve this functionality. The auto unit requires three, to operate all three sets of flaps independently. This is why the retrofit kit comes with two extra stepper motors (actuators), and IIRC one to replace an existing actuator. It also comes with an extra gearing mechanism to improve the mechanical control over the sets of flaps. 

It seems pointless to engineer two different sets of mechanical flaps. BMW could have designed and built one, but simply control them differently. Still, to move from manual to auto, all that needs to be done is to identify which actuators are required (and their wiring looms) and where they go. That's my next step . It would give you some automatic operation for a fraction of the cost of the $500 retrofit kit and the 7-8 hours quoted by dealers to complete the job.


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## BeemerE39 (May 28, 2009)

I currently have the manual climate controls and would love to install auto climate, someone on e bay told me it only required the digital style panel, too good to be true as expected!! If you do know any way please let me know


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