[toto]

How "free" the service is will depend on the dealer. Toyota doesn't promise that these changes are free, only that your dealer can do them. And it's not covered by the 3/36 warranty.

Many dealers will do it one time for free as a courtesy since you bought the car from them.

If you're already taking the car to them for other service work, then they'll be more inclined to do it without charge.

Beyond that, I'd expect to pay the minimum labor charge (1/2 an hour, if not a full hour) for the work.

 

[toto]

I've sometimes had a similar problem with our Sienna - something in my pocket presses against the sliding door or hatch buttons on the fob and causes a door to open. It's usually a sliding door that I find open but I suspect it has also happened on the rear hatch door since there are a few chips in the bottom edge that might have been caused by the door opening and contacting the garage door. I've never found the hatch door open since it would automatically reverse when it hits the garage door. Maybe the hatch door problem can't happen on recent Highlanders - the parking sensors on a friend's Highlander prevents the hatch door from being opened with the remote when the door is near an obstacle.

The problem with an accidental press thanks to something else in your pocket is very real. I modded one of my remotes to disable the rear hatch door button so it can't open accidentally and hit the garage door. How did your friend find out that that the rear parking sensors could prevent the door from opening? The last thing I want to do is test it with the garage door closed! My owners manual for 2016 doesn't mention anything like this. Maybe they added it in a later model year?

 

[toto]

The 2013 didn't have parking sensors. Maybe there was some misunderstanding there about what was going on.

But it's a great idea - if the car knows there's something behind it, it shouldn't let you open the power back door.

 

[toto]

The owners manual has a section on "Customizations" near the back. Carista can probably do anything the manual says the dealer can do.