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Rear Window Defroster Caused Glass to Crack

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pdx_m3s

Active Member
May 18, 2019
2,086
1,991
Portland, OR
For a couple months now, my rear defroster has only worked on a small portion of my rear window. I think I just found out why. It appears that a portion of the defroster heating element (wire) got so hot that it caused a crack in the window, along with many small stress fractures directly above the wire. After some google searching, it appears others have suffered from this issue as well. I have a SC appointment next Friday, but want to make sure I am "armed" to prove that this was NOT an impact crack.

Has anyone else experienced this? If so, how did it go with your Tesla SC?

IMG_2944.jpg


This person has almost an identical crack to mine: Model 3 Window Cracking in Cold Temperature - Model 3 Club
 
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Lets review the Rules of Tesla M3 Ownership:

Auto wipers, don’t use
Auto high beams, don’t use
Seat heaters, don’t use
Battery, don’t use
AP, don’t use
Voice commands, don’t use
Trunk, don’t open
Spotify, don’t use
FSD Features, don’t use
Rear defroster, don’t use
Car wash, don’t use
Head rest, don’t use
And most importantly...

Don’t talk about the Rules of Tesla M3 Ownership
 
Lets review the Rules of Tesla M3 Ownership:

Auto wipers, don’t use
Auto high beams, don’t use
Seat heaters, don’t use
Battery, don’t use
AP, don’t use
Voice commands, don’t use
Trunk, don’t open
Spotify, don’t use
FSD Features, don’t use
Rear defroster, don’t use
Car wash, don’t use
Head rest, don’t use
And most importantly...

Don’t talk about the Rules of Tesla M3 Ownership

And you forgot the most important rule.
Only look. Don't touch. Don't drive. Opening door is allowed, but only on the Model X and 3.
 
For a couple months now, my rear defroster has only worked on a small portion of my rear window. I think I just found out why. It appears that a portion of the defroster heating element (wire) got so hot that it caused a crack in the window, along with many small stress fractures directly above the wire. After some google searching, it appears others have suffered from this issue as well. I have a SC appointment next Friday, but want to make sure I am "armed" to prove that this was NOT an impact crack.

Has anyone else experienced this? If so, how did it go with your Tesla SC?

View attachment 519286

This person has almost an identical crack to mine: Model 3 Window Cracking in Cold Temperature - Model 3 Club

I don’t see how they can argue. Look above and below the wire where the crack is. More damage along that wire.
 
Had the exact same crack last month. No issue they replaced the rear glass under warranty. But......they replaced it with one of the early glass panels that had a red tint when wet. So it made my 3 month old all black car into a black/red car. Ugh. Be careful to ask for matching panels.

Fortunately that panel has a crack on the edge. I’ll be getting it swapped again and this time I will demand the matching glass that came with the car. Fingers crossed
 
Thanks all. Sounds like a problem Tesla is aware of and shouldn’t hit any snags with replacement under warranty. Good call on making sure the new panel matches! I like the red/orange glass panels, but only if they’re a matched set.
 
I had the rear glass replaced under warranty for the same reason. They tried to reject my claim initially and blamed it on my tint, but there are so many reports of this happening that I emailed my SA. No questions asked after that, but thought it was pretty interesting that they tried to pull a fast one over me. Got the 3 back 2 months ago and have not had any issues. I did notice that the rear glass gets pretty darn hot with the defrosters on. You guys should do a test. Turn the rear defrosters on and wait about 5 minutes then touch the rear glass....it's pretty hot to the touch.
 
Had the exact same crack last month. No issue they replaced the rear glass under warranty. But......they replaced it with one of the early glass panels that had a red tint when wet. So it made my 3 month old all black car into a black/red car. Ugh. Be careful to ask for matching panels.

Fortunately that panel has a crack on the edge. I’ll be getting it swapped again and this time I will demand the matching glass that came with the car. Fingers crossed

Good luck with that! Yeah I had to get mine replaced and the same exact thing happened. They use 1-3 suppliers to source the glass and they all have the same part number. Also, almost all seem to be making the bronze hued one that turns orange when wet. Long story short over the summer of 2019 my glass got replaced not once but twice due to them constantly misaligning it. As a result they replaced it for a 3rd time, but it too had issues in terms numerous broken defroster lines. Finally, on the fourth attempt I was shocked to actually see that somehow they were able to match the glass to the original black tinted color. Aligned perfectly as well. Anyhow, you can always request that they match the glass but ultimately they will use whatever part is available. Oh one more thing, they've overtime increased their fault tolerances in terms of gaps and other misalignments. 4mm is within company guidelines. Now this isn't such a big deal when it comes to panels maybe but for glass it looks awful and may even lead to increased cabin noise.
 
Lets review the Rules of Tesla M3 Ownership:

Auto wipers, don’t use
Auto high beams, don’t use
Seat heaters, don’t use
Battery, don’t use
AP, don’t use
Voice commands, don’t use
Trunk, don’t open
Spotify, don’t use
FSD Features, don’t use
Rear defroster, don’t use
Car wash, don’t use
Head rest, don’t use
And most importantly...

Don’t talk about the Rules of Tesla M3 Ownership
So yeah don't have an issue with any of those working. But i never go to a car wash. Uugggg
 
Forgot to post an update. The Portland SC replaced the rear glass same day. They used the matching (non-rainbow) glass.

This is the third time I’ve had my Tesla in for service at the Portland SC, and each time I’ve been very satisfied. It’s really fast to get in and out and no BS.
 
I had the rear glass replaced under warranty for the same reason. They tried to reject my claim initially and blamed it on my tint, but there are so many reports of this happening that I emailed my SA. No questions asked after that, but thought it was pretty interesting that they tried to pull a fast one over me. Got the 3 back 2 months ago and have not had any issues. I did notice that the rear glass gets pretty darn hot with the defrosters on. You guys should do a test. Turn the rear defrosters on and wait about 5 minutes then touch the rear glass....it's pretty hot to the touch.

I can see tint film holding in heat and causing the glass and wires to overheat and crack the window especially if it’s very cold outside. Our low-e glass windows on our house came with a warning not to install any window tinting on them. From what I recall it could cause excessive heat in the air channel between panes and cause the seals to fail.

When the car’s Climate is set by the app to HI and the fans are in full force moving hot air in the car, it really does quickly warm the car to a nice toasty temp. I’ve had my car with frozen rain on it and it get’s defrosted quickly.
 
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I can see tint film holding in heat and causing the glass and wires to overheat and crack the window especially if it’s very cold outside. Our low-e glass windows on our house came with a warning not to install any window tinting on them. From what I recall it could cause excessive heat in the air channel between panes and cause the seals to fail.

When the car’s Climate is set by the app to HI and the fans are in full force moving hot air in the car, it really does quickly warm the car to a nice toasty temp. I’ve had my car with frozen rain on it and it get’s defrosted quickly.

Yes, but there are people who have the grass crack without tint. So this argument by Tesla is invalid.
 
Good luck with that! Yeah I had to get mine replaced and the same exact thing happened. They use 1-3 suppliers to source the glass and they all have the same part number. Also, almost all seem to be making the bronze hued one that turns orange when wet. Long story short over the summer of 2019 my glass got replaced not once but twice due to them constantly misaligning it. As a result they replaced it for a 3rd time, but it too had issues in terms numerous broken defroster lines. Finally, on the fourth attempt I was shocked to actually see that somehow they were able to match the glass to the original black tinted color. Aligned perfectly as well. Anyhow, you can always request that they match the glass but ultimately they will use whatever part is available. Oh one more thing, they've overtime increased their fault tolerances in terms of gaps and other misalignments. 4mm is within company guidelines. Now this isn't such a big deal when it comes to panels maybe but for glass it looks awful and may even lead to increased cabin noise.


Hey FCB. Any chance you could tell me what service center you used when you finally got the black colored glass. I’m having issues with my local service center finding one that is black. So I’m going to try to help them out by calling around. Lol