Bob 
2018 Toyota Highlander SUV XLE 4dr SUV (3.5L 6cyl 8A)
Door lock actuator failer
 The Vehicle's good and bad are very much covered by other reviews.   But......    I have 2018 highlander XLE that is less than one month.    A couple of days ago, when I press key fob to lock the doors, it doesn't beep nor flash lights (Unlock is okay).      I couldn't figure out what setting made that happen.    At the first I thought it is just setting that I need to change, but further research revealed it is failed door actuator issue.    By reading, http://www.landerfan.com/archives/door-lock-problems-toyota-highlander/   , this problem has been going on several years and still happening.    I'm disappointed Toyota hasn't addressed this issue all this years.     :(