Aussie Alan 993

Hi, I am looking for help or information about the unexpected shattering of the rear glass on a 993 Carrera.

I have owned the car for less than a week and have already seen 2 rear screens shatter in my car.

I suspect that it has something to do with the top mounted brake light as it was disconnected and I reconnected it.

Has anyone ever had this experience, HELP Please!!!

Alan

TomF

This sounds like a frame issue. Has your car ever been in an accident? Also, are you using factory Porsche OE glass?

RS man

Would this be something to do with the 18-inch wheels leading to the blowout of the rear glass in the earlier model cars?

Harry

Jeff96-993

I believe there was a TSB relating to Turbo models on this problem... not sure why the Turbos would/could be different, as I think other non-turbo folks had similar issues.

Vinny '98 3.8 C2S

My rear glass blew a couple of months ago right in front of Pocono before a PDA event. My car had been in an accident at Summit Point earlier in the year and I imagine that the two are related.

The shop that does the work on my car said that "it is not that uncommon" (however that's interpreted).

In any case, two breakages in less that a week sounds like frame damage as Tom mentioned, or an improper install on the first replacement.

chris walrod

Other than a 1.21 gigawatt stereo system in the car, I can only imagine the window frame is dimensionally out of wack? Have a close look at the channels the window sits in and make sure they are clean and no rocks or hardware applying point loads on the edges of the glass....

neunelf

I think your right.

I'm surprised that no one else yet remembers this issue.
It's been a while so I am a little fuzzy but I think it did have something to do with the wiring from the brake light shorting out and shattering the glass. It was rare but occured enough that it was a know issue for a short time when the high glass mounted brake light was first produced.

Aussie Alan 993

Thank you for the responses, this is great...

I have been a very busy boy in the last 24 hours and have found out that Porsche have 3 TSB's about the rear glass of the 993.

1. They changed the part number of the rear glass mid model, the new glass p/no is 993 545 107 13. For some reason, possibly noise reduction, the glass was made thicker.

2. They recommend NOT using the existing conductors in the glass, even for the newer version of the glass. Instead they recommend running 2 wires around the screen effectively bypassing the circuit in the glass.
The demister is not a problem.

3. When installing a rear glass, ensure the wiper stem is central in the hole to avoid the possibility of the glass being damaged by the metal of the spindle.

I also found out that if a "New" glass is installed at a Porsche dealership, I will get a 2 year warranty.

Further to this I had the shop guy remove the broken glass and keep the top part of the shattered glass where the black and brown wires are soldered on the the metal track that carried the current round the glass. Sure enough the urethane was a bit burnt and that told me that it was the cause of the breakage. I believe that although it was not a direct short there was enough current to heat that point on the glass but not enough to blow a fuse.

Unfortunately, the glass he put in had the same problem as my original.

I would be interested to hear of any other cases of unexplained rear glass breakage on 993's, I'm not saying it can never be frame damage but be aware of the possibility if electrical damage, especially if the third brake light is not working at the time.

Thanks again for the responses.

Aussie Alan
Sydney Australia

24FPS

there was also a problem with the rear-defroster electrical malfunctioning. esp. in earlier model 993s. heard @ times the switch would occasionally stay "on" while car was parked... eventually blowing-out the rear window. (may want to check w/ dealer re: your defrost switch) ---- just a thought....

bol getting this cleared up.

cheers!

Aussie Alan 993

Thanks, will do...