JoeD-C8

Did a search here but couldn't find answer to my question.

If a side door opens and window does automatically lower itself down low enough to facilitate ease of closure, why can't our cars be programmed so that when the rear hatch is open one of the windows would also lower itself down and then raise up AFTER the hatch is closed, which would facilitate the ease of closure.

As I said I searched here and couldn't find any answer.

iclick

From GM's standpoint I think it's a safety issue, like a kid's fingers or a dog's nose being at risk when the window goes back up. The indexing feature only opens the window ¼", IIRC, which isn't enough to produce much risk for injury and it's only in effect for a very brief time. To allow for my hatch to close, both windows must be down at least an inch, probably more.

defaria

They fixed it in the 2016 using another method.

JoeD-C8

Anyone know what they did to remedy this?

LIE2ME

They brought back the electronic trunk pull down feature that was on the C6....

JoeD-C8

Makes one wonder as to the reasoning for omitting it for the few years.

iclick

Their claim was to save weight, but since the motor reportedly weighs <1 lb. I think it might be reasonable to assume that cost-savings might be the more compelling factor.

Curahee

After over 2 years, I've become used to leaving the driver's door open when closing the hatch. It's become automatic. No biggy.

JerryU

My September 2013 build C7 hatch will not latch even if I slam it hard when closing by the GM handhold. I've tried all of the adjustments and GM recommendations and checked to see that the vent is functioning-it is and no help. It closes and latches easily with very little force if I stand behind my open door and close the hatch from the side. No big deal, I have learned to remember to do this in 2 ½ years! Or I use my Window Valet and open and close the windows with my Key Fob, very useful in the hot summer.

GM hyped their patented “memory wire” activated vent as a weight savings when they introduced the C7 (turned out that was only about a pound!) It was no doubt also cheaper than the motorized pull down latching system in my C6 and what they reverted to for 2016. Cost savings was probably the main reason!

In fact some cars did work as designed but many did not. Some who pushed to latch encountered paint cracking and two reported on the forum worse, cracked hatch frame! I watched my hatch frame bend excessively when I tried to press to latch and decided not to do that!

At a Bash several years ago Tadge addressed the question "Why not open the windows further?" He said for safety reasons they are not allowed to close the window automatically if it is opened more than 1/4 inch, which is the amount they use to get a good window to weather stripping seal. In the only GM dealer bulletin I have seen regarding testing hatch closing it said, "Lower both windows 3 inches and if the hatch latches tell the customer it is working as designed." Assume they are expecting slamming to work. It did for some cars but not for many others, hence reverting back to what was in my C6! (I'm sure after trying hard to get the "memory wire" vent to work. Love to have listened to those engineering discussions about how it was tested and why some cars work as designed!)
Happiness Is An Air Tight Vette!!

Boiler_81

See the first item in the list. The memory wire was a good idea which was poorly executed. It appears as if the vent was not sized appropriately.

http://blog.caranddriver.com/10-awes...e-c7-corvette/

JerryU

Yep lots of GM hype when the car was introduced. If you calculate the area of what the 2015 GM dealer bulletin of suggesting it be tested by opening both windows 3 inches, that is many times the memory wire vent area. To match that area would take a lot of rear space and would not be practicle.

You can watch the memory wire vent open and close by removing the license plate and looking thru the large opening behind it. Use a flsshlight and look to the upper left. With the hatched closed press the open button above the license plate and you can watch the vent open. It stays open as long as the hatch is open.

My guess is it probably worked on the 100 or so prototype IVERS they drove for almost a year before the car was introduced and 1 1/2 years before the first production build. Those cars were probably not as air tight as some production cars. In fact I wonder if the cars where the hatch "latched as designed" were less air tight, for whatever reason than those of us where it will not latch?

CriticalmassGT

I suppose you could do that, but at least you know that the car is pretty air-tight when all the windows are up and you are closing the hatch. Cuts down on road noise.

JerryU

As I stated in post #9, Tadge at a Bash said that they were not allowed to have the windows automatically raise more than the 1/4 inch they use now to get a good window to weather strip seal. Don't recall if that was a GM or federal safety spec. That is a pinch point. If a child or dog was in the car their finger or head could get pinched!

Steve Carter

It's a problem on the 14's & 15's but I over look this knowing the car is "air-tight"

I have two different hard tops and I'm pleased both have this "problem" The fix on my 2013 Z worked well and I'm sure the guys with the 16's and newer C7's wonder what the fuss is about. I'm happy for you guys with the GM fix but you miss the air-tight joy we have in the older ones.

Formula52

I have a 2015 and at first it was a pia closing it 2 or 3 times until I got the right amount of pressure to close it on the first try (which was a hard push).

But now after a year, it closes like butter. I need very little pressure to close it on the first try. So the auto pull down is a non issue for me...

roadbike56

My '14 still won't close with the doors closed and windows rolled up. It's a PITA, but if this is the biggest problem the C7 has, I can live with it.

Flame Red

I emailed Top Down Technologies, maker of the Window Valet with this "need" top crack the windows when the hatch it opened but no response. Maybe others in the forum could add their voices and if enough of us ask, perhaps they will see the demand.

There was another member that bought all the 2016 parts and was trying to retrofit them, but he has not apparently succeeded.

There was a thread on the Z06 section about developing a Window Valet type device to do this and turn on the PDR on engine start but no action there.



Anyone try tinkering with the mechanism? Like trying to prop it open longer or making it larger?

JerryU

Yep, some cars worked like the salesman showed in the 2013 video he made! Just why has never been explained by GM. Mine will be 3 years old in October and no matter how hard I slam it will not latch with doors and windows closed. However with my door open I can stand directly behind it and it closes and latches from the side with little force!

I pressed to latch when I got the car in October 2013 and watched the bottom of the hatch frame flex excessively.. Since my tech expertise is materials I stopped. Soon after folks were told at Museum Delivery not to press from the center as there were reports of paint cracking! In 2015 to separate forum posts mentioned the hatch frame cracking from pushing to latch!

For those where it closes and latches with minimum force as GM designed - fine. But for some cars the safe way is to have a door (or windows) open.

It's second nature for me now so no big deal. In fact you're either: 1) getting out of the car when your going to open the hatch so leave the door open and close it last, or 2) if putting in groceries etc, leave the hatch open, open your door then close the hatch first!

Helps train your short term memory some of us old folk need to practice!

JoeD-C8

Not to get off the subject but as a previous BMW owner there were people who would write programs for windows half up, what lights would blink with certain functions. You name it and someone was writing a program for it Still don't see why a simple program to trigger a partial window retraction when the hatch opens and closes that same window after hatch is closed. Maybe the younger, more computer savvy crowd? Not sure.

JerryU

Good point. Even if it's something the federal specs don't allow in the US, like convex driver's side mirrors, the aftermarket is usually not held to those standards. There would however be liability for the manufacturer if a child or dog got there head stuck!

The Window Valet provides a similar function now. It is safer since you have to press the key FOB lock and unlock buttons three times to open or close the windows. So if your dog has his head out the window you wouldn't press the FOB! Safe and you can buy it now.