Shattered rear windscreen

[steve2003rs6]

Had both screens removed to have roof rail repairs done and some new paint.
Took the opportunity to renew both screens.
After the new screens had been installed decided to Leave the car overnight to allow bonding to cure.
Next morning went to fill up with petrol and bang. Rear screen shattered and glass everywhere. Yet another screen fitted and should get my pride and joy back tomorrow.
Question is. Has anyone else experienced a new screen exploding for no apparent reason.

[Mark-RS]

Not heard of it before, only thing I can think of is that it was incorrectly fitted ? Being bonded they are structural I think ? If put under tension, or twisted due to chassis flex could shatter it ? Strange it happened when sitting still though ?

[magpie21]

Argh what a nightmare, were you able to claim through windscreen insurance or do you have to pay for it yourself?

[steve2003rs6]

Thanks for the replies guys.
So wasn’t sitting still had gone down the road to fill up with petrol. Been driving for about 5 mins. Put rear screen heater on to demist the window and 2 mins later BANG.
The screen installer (with 50 years experience) said that it had never happened to any screen he had installed before.
Guess I am just lucky ??????
Thankfully the manufacturer provided a replacement free of charge.
Spent most of yesterday hoovering the car out the glass fragments were everywhere.
Get the car back tomorrow
Cannot wait as she really is looking superb with the new paint and all over machine polish.
Car in garage next week as well for a routine gearbox service.

[steve2003rs6]

Ps this is why we took the windows out. So pleased we did as we would not have noticed the rust patch on top left corner under the glass.
Apparently just caught it in time for a effective repair to be done.
You can just about see the paint starting to bubble on roof front left edge on the second picture.

[steve2003rs6]

Repaired painted awaiting installation of a new windscreen.

[steve2003rs6]

Just been to collect the car. Before we moved it. Put the rear screen heater on to test it.
Second brand new rear screen has exploded. Absolutely gutted.

[Nobby]

Wow that is weird.

I hope it’s not a problem with screen demister - is it possible for it to get too hot?

[srichards]

Sounds like the screen demister shouldn't be used. Was it on when the first original one failed?

[steve2003rs6]

Hi guys. With original screen everything was working fine. Never ever had a problem.
Both new screens got red hot on near side and cold on offside then shattered. Going to check voltage before we reinstall the original screen. Will let you know what the outcome is.

[steve2003rs6]

Help. Does anyone know what voltage should be going to the rear screen heater. ?

[steve2003rs6]

Put the old screen back in. Everything working as normal. Left heater on until it automatically switched off.
Resistance on original screen 0.2
Resistance on new screen 3.8.
Measured voltage (car running) 13.8 to 14 v
At least we are nearly there. And proved that the new windscreens were at fault.

[srichards]

Yep. Must be a manufacturing fault. Worrying for anyone that gets a replacement rear screen.

[steve2003rs6]

Yep. Must be a manufacturing fault. Worrying for anyone that gets a replacement rear screen.

Yes that’s what I thought.
Been a very expensive learning curve.
Old screen back in tomorrow. Another morning hoovering out. The shattered glass goes everywhere. Then another good machine polish.
Hopefully that will be it.
Besides getting my money back for the crap screen.

[IchBautAuto]

This should be a sticky. Do you remember the brand of screen. I'd never have thought about needing to check the resistance of the heating element, such a basic component.