I purchased my wife a 2017 QX80 limited edition not even 3 weeks ago and the brakes went out. She happened to be talking to me via bluetooth while she was getting ready to pull out of the parking lot of her leadership forum meeting and I heard her say, "Whoa Whoa wait". I asked her what was going on and she replied the brakes aren't working. Of course my reply was, "Whatdya mean the brakes aren't working?". She turned off the truck and restarted it and again the exact same thing occurred. THANK GOD she was on ly going about 5 mph as it could've been detrimental or even fatal had she been driving on the freeway with our son. The brakes went ALL THE WAY DOWN THE FLOOR. .... When the Infiniti tow truck driver brought it in with my wife I was waiting at the dealership. My wife asked as the tow truck driver was taking it off the flatbed, "Is it still doing the same thing as when you uplifted it? and he stated, "yes mam' the brakes are still going down not just as much, but it's still doing it." At this point it's at the dealer and a ticket\case has been opened as they're saying this has never happened before and they're awaiting an engineer to come out and review the vehicle b/c at this time it's miraculously isn't doing it anymore and they can't seem to find why or even how it transpired seeing as though no diagnostic codes are populating. Now when we brought in the vehicle, it was about a little past 6pm due to rush hour traffic on Thursday. However, the service dept.didnt take a look at it until Sat. which gave whatever causative actions time to reset itself, if that's what happened. We are waiting to hear what engineering findings are and our dealership has assured us that they will NOT let my wife and family drive this beast of a vehicle and possibly jeopardize their lives in the event the engineer doesn't find what caused this to occur initially. Will keep the forum posted as to what happens next....