My 5bw had this issue. I have an identical video. Documented a few things, so thought I'd share. This triggered a TAC Case as GM was very interested in this issue.
Took it to the dealer two times, as after they replaced the hose the issue reoccurred after about 100 miles of driving.
The car hasn't had any issue since the last service. Finally feel like I have my "new" car, and can drive it right without worrying about some shit going wrong. Bummer for new cars to be in the shop with essentially a Quality Control issue from factory, but many on here have had similar experiences with other issues. Hence why I'm sharing. In fact, I shared the info regarding the Air Bag Sensor issue (loose connection behind the steering wheel - and the Service Manager said, he appreciated that I mentioned that, because it was in fact where the issue was, so they didn't have to dig and troubleshoot with the info provided by me which I gained form THIS forum Thanks
@Rob and others )
Here is the service work notes(I chuckle at how they translate the customer statements and actions):
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Description of the screenshot of pictures below(didn't feel like posting all those pics and vids, so it's a collage instead):
Dot4 reservoir (seems important for hoses not to be disconnected and dangling) eh?
The rubber adapter and plastic hose connection was breaking with the pressure. It wasn't leaking everywhere, somehow, but the fluid level was near Min Level. I 'secured' the connection before driving it to the dealer the second time.
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