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Sunroof function question re: express open

6003 Views 36 Replies 8 Participants Last post by  Chipshot
Is there a reason that the one-touch (or express) open function does not fully retract the glass?

It seems pointless that I have to press the glass open button twice (or hold it) to get to the fully open position. It’s certainly annoying.

I mean, could it be a safety feature to prevent wind-blown “hyper-extension” or something?

I don’t get it.
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Is there a reason that the one-touch (or express) open function does not fully retract the glass?

It seems pointless that I have to press the glass open button twice (or hold it) to get to the fully open position. It’s certainly annoying.

I mean, could it be a safety feature to prevent wind-blown “hyper-extension” or something?

I don’t get it.
You are probably holding the button down too long. Just a short stab puts it in full open mode. If you hold it, even for one second, it thinks you want to control how much it opens. During my familiarization session the dealer specifically pointed out this Alfa quirk to me.
It's more like "most-modern-cars" quirk, actually -- YES, they do it on purpose.
Several car makers are putting in an automatic "preferred" open position for optimal aerodynamics in order to minimize noise, and it wouldn't surprise me if there was some academic mileage improvement they could claim to keep the regulatory bastages appeased. Try the "preferred" and fully open position back-to-back on a stretch of about 40-50 mph road and you should see a noticeable interior wind/noise difference. I think with the "exterior" roof on the Giulia, the difference is a little less pronounced, but on a 2007 A4 I had for many years with the retracting/interior roof, the difference was astonishing.

Besides, how often do you drive around with your right-seat vehicle commander standing up out the sun-roof?

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You are probably holding the button down too long. Just a short stab puts it in full open mode. If you hold it, even for one second, it thinks you want to control how much it opens. During my familiarization session the dealer specifically pointed out this Alfa quirk to me.
I did double-check and that's not what's happening, but are you saying you have 1 touch full open functionality?

Mine closes with 1 touch, but it does not open fully with one button press.
It's more like "most-modern-cars" quirk, actually -- YES, they do it on purpose.
Several car makers are putting in an automatic "preferred" open position for optimal aerodynamics in order to minimize noise, and it wouldn't surprise me if there was some academic mileage improvement they could claim to keep the regulatory bastages appeased. Try the "preferred" and fully open position back-to-back on a stretch of about 40-50 mph road and you should see a noticeable interior wind/noise difference. I think with the "exterior" roof on the Giulia, the difference is a little less pronounced, but on a 2007 A4 I had for many years with the retracting/interior roof, the difference was astonishing.

Besides, how often do you drive around with your right-seat vehicle commander standing up out the sun-roof?
I'll have to check out the wind management theory. It seems like it would be kind of random to decide to design it that way, since there are so many variables (such as window positions) to affect things, but I'll try it out. It would be nice to know there was reason for the sunroof to operate like it does.
The complaints I see sometimes here are so funny, how hard is to press it again to fully open every car I have owned so far did this, 2 vws, 2 nissans, mercedes, jeep, honda, audi.
I wish I could find humor in the absence of curiosity in others, but it seems so much more serious than funny.
I did double-check and that's not what's happening, but are you saying you have 1 touch full open functionality?

Mine closes with 1 touch, but it does not open fully with one button press.
I checked and it is like yours - it opens half way some times, and 3/4 other times. I have no idea what Alfa's logic is for this.

I don't open the sunroof much in the summer -- it's too hot here in the South.
The complaints I see sometimes here are so funny, how hard is to press it again to fully open every car I have owned so far did this, 2 vws, 2 nissans, mercedes, jeep, honda, audi.
I did not see @chaadster's post as a complaint, but simply wanting to know why it does this seemingly incomprehensible thing. I'm now curious why, too.
The complaints I see sometimes here are so funny, how hard is to press it again to fully open every car I have owned so far did this, 2 vws, 2 nissans, mercedes, jeep, honda, audi.
I did not see @chaadster's post as a complaint, but simply wanting to know why it does this seemingly incomprehensible thing.
I'm now curious why, too.

Mine opens to the same point everytime than i press again to go into full open mode, if yours is doing that there is a reset procedure you can do, mine didnt open on 2nd day of ownership because i was messing with it first day, so I reset it and it has been great every since.
Agree with prior posters: 3 operations: first short push: opens to "optimal" opening for minimal noise and wind (about 3/4 of the way open). Next short push opens the window fully. If instead of a short push you hold it, it will keep opening until you stop pushing, allowing you to open it to whatever position you want. My prior vehicle (Cadillac CTS) operated the exact same way.
I'll have to check out the wind management theory. It seems like it would be kind of random to decide to design it that way, since there are so many variables (such as window positions) to affect things, but I'll try it out. It would be nice to know there was reason for the sunroof to operate like it does.
Yes there can be many variables but it doesn't really matter because they are not trying to cater to all of them. They are trying to avoid a specific scenario, namely a large air pressure differential inside vs outside. This pressure differential and the associated buffeting noise can actually be physically painful to some people's ears. The most likely scenario for this to occur would be with windows closed, roof open, and with speed fast enough to generate air pressure differential.
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Yes there can be many variables but it doesn't really matter because they are not trying to cater to all of them. They are trying to avoid a specific scenario, namely a large air pressure differential inside vs outside. This pressure differential and the associated buffeting noise can actually be physically painful to some people's ears. The most likely scenario for this to occur would be with windows closed, roof open, and with speed fast enough to generate air pressure differential.
Yes, that’s a possible explanation, but questionable given that sunshade opening functions the same, even when the sunroof is closed, so wind management cannot explain the two-press behavior in that case.

I’ll try out the buffeting thing here today and see if that might explain it.
Most modern cars with large sunroofs operate in the exact same manner, it's to cut down on wind noise. My Giulia operates the exact same way as yours, it's not a problem/defect or anything else.


Try a few other car brands and you'll find they do the same.
I did two out-and-back runs at each position with side windows up, down a mile long stretch of road at 50mph, and did not notice a meaningful difference in wind behavior between the one-touch open position and fully open.

Between that and the sunshade opening behavior, I'm inclined to think there is something other than wind control going on.
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I did two out-and-back runs at each position with side windows up, down a mile long stretch of road at 50mph, and did not notice a meaningful difference in wind behavior between the one-touch open position and fully open.
Maybe try it with a rear seat passenger?
Maybe try it with a rear seat passenger?
I know, right!
I did two out-and-back runs at each position with side windows up, down a mile long stretch of road at 50mph, and did not notice a meaningful difference in wind behavior between the one-touch open position and fully open.

Between that and the sunshade opening behavior, I'm inclined to think there is something other than wind control going on.

Try it again above 60. Fully open it's windy in the car, more so with a window down. It's not a conspiracy, most cars do this.
Try it again above 60. Fully open it's windy in the car, more so with a window down. It's not a conspiracy, most cars do this.
Helmholtz resonance.
Try it again above 60. Fully open it's windy in the car, more so with a window down. It's not a conspiracy, most cars do this.
I'm not talking about a conspiracy, just asking why!!

Is 60mph meaningful, or just some number you pulled out arbitrarily? I'd be surprised if they were engineering wind management for sunroof use at highway speeds; doesn't seem like that would be a common use scenario, although I have done it, but not with the windows up.
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