Broken rear windscreen - A4 Avant

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Mon 1 Dec 2003 10:51
Broken rear windscreen - A4 Avant - bananaman
When we came back to the car from a shopping trip on Saturday I noticed that the rear windscreen had been broken. What was odd was that it didn\'t look like a break-in attempt. The damage was thus.

There was a large crack running the length down both sides of the windscreen. At both bottom corners there were identically sized holes, about 15cm across. The screen itself looked like it had been pushed out not in. The glass broke off very easily with any movement. This and the fact that the holes were small and the luggage cover was still in place suggested to me that the break was caused either by the air pressure generated when closing a door or the actual shutting of the boot.

Has anyone had experience of a similar occurence?

PS The car is an A4 Avant and the doors generally need a good slam to shut. The exception is the boot which I let close under its own weight.
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Mon 1 Dec 2003 11:03
Broken rear windscreen - terryb
Saw it on a Citroen Saxo about a month ago. Lady driver said it happened when she shut (slammed?) the door, so I reckon your theory on internal air pressure isn't far off the mark.

Terry
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Mon 1 Dec 2003 15:32
Broken rear windscreen - AR-CoolC
At both bottom corners there were identically sized
holes, about 15cm across.


This would sugest to me that there has been some sort of a problem with the heater connectors (are they in the same area as the holes ??) if you can see them take a look at the connectors and see if they appear to have been getting too hot. This is often the cause of apparent breakage for no reason.

I would be very supprised if the air pessure from closing doors had caused the glass to break !!

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Mon 1 Dec 2003 15:54
Broken rear windscreen - frostbite
At both bottom corners there were identically sized
>> holes, about 15cm across.

mm I hope! Go with g-t on this one - seen exactly that on a mate's motor.
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Mon 1 Dec 2003 16:06
Broken rear windscreen - bananaman
The car is at the glass fitters waiting for a new rear window at the moment. When it comes back I'll see whether the cracks down the window at the side correspond to the heating elements.

Should I take it to the Audi garage to have a look?

The Audi is pretty well sealed, with double door seals, and no air comes through the air vents with the air con off. If you shut the doors the rear tailgate is lifted up if left slighly open so some pressure is generated. However, air is pretty compressible so yes I agree it is probably unlikely to have caused the breakage. Although it may explain why the glass looked pushed out.
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Mon 1 Dec 2003 21:24
Broken rear windscreen - DL
Ah...the old heated rear window breakage! Common fault on some cars - which will remain nameless.....

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