When I bought my IS350 they only had 1 key for the car. My wife has a 2016 Highlander with the same style key system. I have asked the dealership, and they said that you can only control 1 car per key. They did not testing or checking. I don't care if the buttons on the Toyota key work. I would just like to start, unlock/lock with handle, with her key also. I wonder if her key can be programed to start her car and mine.

 

I've never heard of any key being able to control 2 different cars

 

highly doubt that.

 

I am not sure if the key has 2 way communication or just one way. Does it just tell the car that they are authorized to be used, or does the car talk back to the key telling it what car it will only work on.

 

I believe the way it works is a key-fob is programmed for a car's digital code and a key can only have one code.This code generates new digital keys and that one code keeps the key sync'd with the car. I could be wrong but I am pretty sure the answer to your question is no.

 

Key was still in my possession but I did not know where the car went!