Just had my 2002 RX300 inspected and oil changed. Week later VSC, Trac Off and engine light lit up. Mechanic replaced oxygen sensor. Two days later the air conditioning stopped working. What's going on?

 

Welcome to the Club. I moved your post into a separate thread of its own. Air conditioning is an independent system of the other issues you mentioned. Can you describe for us when you first noticed it went out (were your driving, just starting up the vehicle, etc.?)

 

Check the fuse for the a/c and see if it is okay.