Is it normal for rear windshield to break on its own????

Rare but I think there could be a few prior posts last 5-6 years or so about front windows shattering due to temp changes. You know what they say, memory is the first thing to go, or is it the second thing?

 

Rear defroster use?

 

On some cars it’s somewhat common for window heater wire connections on glass to have bad contact to the actual heater. This will make that one place hot. And glass being hot on one spot and cold on others breaks it.

 

I would just like to add that I had the lower rear glass shatter upon closing the hatch of my 2017 with normal impact. I was not aware of anything that had happened to weaken that narrow piece of glass. I thought I would try to argue with Toyota about it to be covered under warranty, but my insurance coverage is 100% for glass with no deductible, so I am taking the easy way out. This is my second Prius, 2017 level four, two months old. I had been driving a 2010 for the prior four years, no glass incidents!

 

That is interesting. Since you have a Gen 4 Prius, you should start a new thread in that forum.
I have heard of the windshield on Two ECO and up having windshield breakage issues, but not any rear window. My small rear window stays so dirty it is almost useless.

 

Came home 2 days ago and this is what happened 20 mins later. It was cold outside. Breaks at 07:46:16

 

Did he contact his insurance company?