Ghost door unlockings or hatch openings have "magically" occured on occasion....also on my Highlander.. ..usually every time the wife rearranges or shoves another piece of crap in her handbag and jams it shut.

 

Other strange thing was this was the first time ever where Toyota app displayed a location OTHER than where the Venza was actually parked. Like 17 miles away where it had been parked earlier in the day. Just seems funny how both things occurred while Toyota had a software update in progress or planned overnight. Maybe some kind of electrical gremlin at work temporarily.

 

"... there was a notice yesterday for a software update, which Toyota activated at 2 a.m...."

I don't think Toyota pushes vehicle operation/functionality related software updates "over the air" other than Infotainment Updates. Unlike Tesla. I prefer Toyota's philosophy. Less chance of "bricking" the entire car.

 

How near to the vehicle are the key fobs when it is parked?
I've found the range on our new fobs to be much better than the '16 Corolla and '15 Rav4... I can operate mine from at least 100ft line of sight.
The smart-lock functions require the fob to be within a few feet, so this would not have been from someone attempting to open it with the fob in range. It would have to have come from a button press.

I've also triggered the lock button with a wrinkle in my pocket while getting out of the car.
It's possible that the fob was inadvertently triggered by someone in the home.

 

Checked all possibilities. First, opening the tailgate requires one quick press of the fob, and then a hold down press for two seconds to actually start the tailgate up or down. Tailgate and doors were closed and locked when Venza was secured at about 7 p.m., and fob activation will not open tailgate from inside the house. Even outside, I have to be fairly close to the Venza to get the tailgate to open. The unlock function for the doors activates at about 40 feet, much quicker than the tailgate. As I said in a previous post, I find it strange that this occurred when an update function activated at 2 a.m., and at the same time, the Toyota app on my phone showed closed and locked, yet it was displaying info with a location I was at earlier in the day, about 17 miles away. I know nothing about the frequency that the fob operates on, but is it even remotely possible that a garage door opener could be on the same frequency? Probably not. Anyway, if it happens again, then there's an issue. If not, probably just a one time aberration.

 

When you're in for service, or even before that, have them check the button-press parameter for opening that door. We had to have it changed in our Corolla from 1 press to two press and they charged us $132 to do that with their computer. It could not be changed any other way. We would have ordered the car that way when we bought it if we could have guessed there would be door or trunk butt-dials. I would hope there's an aftermarket device for owners to make such mods themselves, and it might be worth owning one of those.

 

Carista OBD2 App | Diagnose, customize and service your car (caristaapp.com)

 

I have never experienced your particular issue, but I had to deactivate my 21' Venza rear hatch auto opening function (kick of your foot). We have 3 Bassett hounds and if I had the key in my pocket and was close enough to the car a wag of a tail or them running under the rear of the car would open the tail gate. At least Toyota allows you to deactivate this function. After the tailgate opened into a closed garage door I had enough and turned it off. Luckily no damage. Wife has a 17' Ford Cmax we have the same issue with. Unfortunately, not even the Ford dealer can turn that one off.

 

With all the electronics these days anything could happen. I agree with you that the failed update probably had something to do with it. We've all experienced weird computer glitches and modern vehicles are no different. The update attempt might have cycled some modules including the liftgate's module which may have triggered it to open. I'm not sure if you can do it but I would disable automatic updates to prevent this from happening again.

 

Good suggestion. I think I will schedule any updates for daytime. They don't usually take that long to download anyway.