Rear Window Exploded! Window defogger to blame?
 

My rear window was foggy this morning so I ran the defogger for about 30 minutes. After I could see the defogger wasn't doing much good, I turned it off. Then about 10 minutes later, on the highway, going about 75 mph when I heard a pop and looked in my rearview mirror to see my back glass completely shattered.

I don't recall how close I was to an overpass, although there could have been one nearby, but I was definitely not under one.
That, in combination with the glass pattern leads me to believe that the window expanded (or contracted) too quickly.

Essentially, the upper corners were completely shattered out, and there was an irregularly shaped tiny hole (maybe BB size?) in the exact center of the window , about 4" up from the bottom, from which the snowflake pattern of cracks radiates.

The fact that I was not under an overpass, and that the hole was located in the dead center of the glass, and that both upper corners shattered out leads me to believe that the window expanded to a point at which it was larger than the opening and simply exploded.

This happen to anyone else? If it is a defroster issue, what are the odds of me getting Mazda to pay for this? Or at least my deductible? B2B is expired, I've got an '04 / 41k mi.

Its pretty hard to get Mazda to cover it since there is almost no way to tell if it was the defroster or you got hit by something.

Just vacuum it and replace the glass, couple hundred bux from safety glass, fix the defroster too. Your insurance might cover glass. so ask.

I doubt it was caused by your defogger... its most likely a fluke thing. check to see if you have glass coverage on your insurance. if you do, they should cover it.

Hmm.... this is suspicious ... 27 hrs prior on the same stretch of road... When I get back from work I will look for a projectile.

http://www.baltimoresun.com/news/loc...,4238241.story

there ya go, file claim with local PD and youre insurance should cover it under vandalism

its hard to proof. unless u find some kind of evidence.

go to a store and buy a thing of BB's... bring one in and say you found it while cleaning the mess in your car..

That is insurance fraud.

Ha, i know this, and if the OP doesn't realize he shouldn't do that, maybe he should get caught... haha...

At least in my state, if you have a lien on the car, you need to have full coverage, which includes glass... file a claim with your insurance company and they'll most likely take care of it

I know this happened to me with a rental car one time in Somerville NJ.
They guy I was on business with like to dick with the defrost all the time. Well, we had stopped at a diner for some dinner one evening and we came out, got in the car, shut the doors and bam! All the glass in the rear had shattered and fell into the back seat. When we heard the bam.....we just kinda looked at each other and said "WTF?", then we looked in the back seat. Hertz wasn't too thrilled, but it was what it was. It had to be the defrost somehow. Anyway..............the really strange thing was that about two weeks later, it happened to the same guy, but this time at home with his own vehicle. Neither were RX's, but it is possible.

insurance fraud ftw

Mazda won't cover it as you're out of your bumper to bumper warranty and you can't prove that it was a defect in the window.

Your best bet is to check with your insurance company for glass coverage.
If they won't cover it, then start calling around for a replacement, shouldn't cost more then a few hundred bucks

It was replaced this evening, just before it started raining. $500 deductible comprehensive claim. I actually just raised my deductible the last time i renewed my policy :doh:. I calculated that unless I smashed my windshield at least once every 3 years or something, it would have ended up costing more than it was worth. Who knew I was about to shatter a $600 piece of glass...

fwiw, I called around to see if I could get it cheaper than my deductible. One place had it for $499 but everyone else was $600+ (as high as $900!)

Moral of the story: don't break your back window, unless you have a low deductible.

thats odd, my insurance doesnt charge me my deductible for glass... i dont pay a dime when i get windshields replaced

True.....that's a state law in Florida as well, but I believe it won't cover your back glass.....which is what he's talking about. Although.......he did make reference to the windshield in his last post, it was the back glass that busted.

ay, my insurance doesn't require any sort of deductible for window glass..

I did a search on Google for "window defroster shattered" and a lot of stuff came up, particularly on Fords, where the rear window inexplicably shattered after defroster use. Does anyone know if we share the same glass company as Ford? I know there's a lot of other interchangeable parts between the brands.

all you need is a policy which covers full glass, regardless of deductible.

I have 500 deductible on my policy(soon will raise, just wait a bit) but with FULL Glass.

so that means, if my window(s) breaks I do not have to pay a penny out of my pocket.

Going for Full Glass policy just cost me like another 40 bux for 1/2 yr I think. pretty worth it IMO.

Well its September 2009 and my 2004 RX-8 rear window shattered. The entire thing. It was parked and I had the moon roof open and windows down a tad to keep the temps inside down as well as a windshield cover inside the front. As I started to back up to go home I noticed the whole rear glass was shattered. Only the tint film I had put on last year is keeping the glass in tact. I could not see any rocks around the car nor did it have any bullet or pellet shot so all I can guess is someone passed the car on the lot and a rock hit it. No proof as the whole thing looks the same to me. Cost? $800 something. Ouch! I didn't ask the dealer figuring they would sub it out to a glass company and place a 100% mark up on it. I checked on here to see if this is a problem with the RX. Makes me mad. Take good care of the car and now this. Bummer

Glass is something that is not interchangeable unless they badge swap, the Tribute and BT-50 Pick-up are the only Mazda sold cars shared with Ford.

Does Ford have a car that looks like the RX-8?..Ahh ...Nope.

The Glass in all imported Mazda's from Japan is made by "Nippon Safety", made in Japan, not the USA.

I have not heard of glass shattering on Mazda's when using the Defroster, could be a possibility. I tend to think you were shot at!..

Sorry to hear about the hassle. :)

wow, what the window.
why don't you try to talk to mazda first??
they might do sth about it
if not insurance??
wish you luck!

The glass pattern he described is evidence enough. A high-velocity projectile like a BB leaves a distinctive pattern at the point of impact.

Here's an example with plate glass. With tempered safety glass, there will be probably be cracks radiating and fragmentation or even the entire window could have shattered.

http://softsolder.files.wordpress.co...ass-window.jpg

Safety Glass in ALL Mazda's is only on the front Windscreen, ALL other glass is not safety and will shatter like door glass into tiny pieces. it won't crack..

Update on my shattered rear window. Cost a whopping $911 bucks!! Seems the dude driving the lawn mower yesterday must have throw out a rock and it just happened to hit my rear window at some velocity and shattered it. Building landlord has insurance and they will pay me back with a check. Seems yesterday two cars were hit by the lawn cutting folks. I was the first claim. You could barely tell but the rock hit on the drivers side and the whole thing cracked into hundreds of tiny glass chunks. The repair guy from Safelite had to vaccum the trunk out as well. The rear shelf looks a little cheaply done to do when you see the car without a window but its fine now. Not sure I am getting the window tint on the rear glass though. I like the clear view in the rear view mirror now. Came up to another Red RX-8 at a red light going home and I beeped the horn and the guy did not respond. It was like he was on the moon or Mars. He was driving slow like the first time I did when I got the RX. Oh well. You don't see too many RX's in Colorado Denver area.

Man that is insane. I cant imagine it just breaking on me