I own a 2005 RX330.Ultra Premium I purchased it used 3 years ago. I have never had any problem with the icon on the dash which lights up when air pressure in tires is low.(Canadian cars have no buzzer, just the icon) The other day while watching my tires get changed from snow tires to all weather, I noticed there were no monitors in the wheels. So the icon lights up when you turn on the key but goes out when the car starts. Was the car like this when new? Can this an easy fix for people whose icons don't go out? I own two other Lexuses where the monitors fail occasionally. I would just remove the monitors in the wheels rather than trying to disconnect wiring in the dash

 

Interesting read here. May answer the question why you don't have sensors in the wheels.

https://www.clublexus.com/forums/rx-...-pressure.html