Have the same problem. Unfortunately took my 2003 300RX to the local Toyota dealer to rotate the tires, another story about those maddening locking lugs. On the way home the same 3 lights came on. Service manager insisted that they did nothing other than rotate the tires. Called the out of town Lexus service manager where we purchased the car. His immediate reply: " Someone has been messing with the air filter." Returned to the Toyota dealership and after a phone call between the two service managers the Toyota manager said:"Of course we always perform a 24 point service check which includes the air filter." After 3 attempts each time the lights are off from 1 to 10 days but always come back on, the Toyota dealership refuses to do anything else. The problem is either un-metered air entering the intake system ie a leak or a bad sensor either way damaged by the service shop. With the exception that the lights are on, the car performs without issue. Of course, the problem destroys the cars resale value, but I plan to drive it 'til the wheels fall off. Lesson: Never take a Lexus to a Toyota service department not even to rotate the tires.
