Windscreen may have cracked when cooling car?

[Flatbat]

Last weekend my Model 3 car was parked in the sun for several hours on a warm 32C day. About to head off so I precooled the locked car remotely, as the app told me it was 57C inside. Shortly later, on the ten minute drive home I noticed a 15cm vertical crack, right in the centre of the windscreen, propagating up from the bottom edge. It was not there on the outbound drive so I assume it cracked when parked and I did not notice it in my pre flight.

Teslafi tells me precooling dropped the inside temp dropped by a 37 degrees! Cooling it from 57C to 20C. It took the first 20 degrees off in 2 minutes flat, then a further 7min to reach 20C. Fan blowing at 9. I am wondering if the temperature shock caused the crack to start & propagate. Has anyone heard of this happening?

I know this sort of cooling event is very common and peoples windscreens are not spontaneously cracking L,R & C. Just struck me as a helluva coincidence. On close inspection I can see very small <1mm pit in the crack about 2cm up from the edge of the glass, right above the windscreen demist outlets. Unlikely place to get a stone chip so low down on the screen but possible I guess. Where I was parked was in a paddock with no lawnmowers nor, anyone about.

Anyway off to get it replaced by Tesla next week. Insurance claim. Crack spread all the way to top now and across the cameras.

 

[Blue heaven]

Last weekend my Model 3 car was parked in the sun for several hours on a warm 32C day. About to head off so I precooled the locked car remotely, as the app told me it was 57C inside. Shortly later, on the ten minute drive home I noticed a 15cm vertical crack, right in the centre of the windscreen, propagating up from the bottom edge. It was not there on the outbound drive so I assume it cracked when parked and I did not notice it in my pre flight.

Teslafi tells me precooling dropped the inside temp dropped by a 37 degrees! Cooling it from 57C to 20C. It took the first 20 degrees off in 2 minutes flat, then a further 7min to reach 20C. Fan blowing at 9. I am wondering if the temperature shock caused the crack to start & propagate. Has anyone heard of this happening?

I know this sort of cooling event is very common and peoples windscreens are not spontaneously cracking L,R & C. Just struck me as a helluva coincidence. On close inspection I can see very small <1mm pit in the crack about 2cm up from the edge of the glass, right above the windscreen demist outlets. Unlikely place to get a stone chip so low down on the screen but possible I guess. Where I was parked was in a paddock with no lawnmowers nor, anyone about.

Anyway off to get it replaced by Tesla next week. Insurance claim. Crack spread all the way to top now and across the cameras.

Possibly the very small chip in the windscreen extended into a 15cm crack due to the rapid cooling. Generally windscreens are subjected to some fairly extremes of temperature without any problems so unless the m3 screens are of average quality I wouldn't expect it to crack without some other influence.

 

[Flatbat]

Yes I agree, seems the tiny chip was most likely the catalyst.

 

[touringsedan]

I had three rock chips on my windshield, one was low, like around the area of the wipers. I meant to fill them with a 3M kit and forgot and the first time I defrosted a huge crack popped between two of them.. sigh.. Now I carry a spare 3M kit to fill them immediately.