Your Lexus has On Board Diagnostics 2 (OBD2). There is a 16 pin diagnostic socket under the dash board. Your cars computer has seen a problem with the vehicles emission control system that may or may not also exhibit a drivability problem. Many things can be responsible for illuminating the Check Engine Light and the computer monitors many sensors for opens shorts and performance. Many of the power train sensors are shared by the traction control system. You will find by fixing the Check Engine Light the TRACTION CONTROL, and VEHICLE STABILITY CONTROL lights will turn off.
Even a pretty generic (non Lexus) scan tool should be able to read the problem.
I have a 2006 Lexus ES330, just bought the car, drove it 1997 miles when all of a sudden the check engine light came on, traction off light came on and the VSV light came on. Checked for codes, got PO174, lean miss fire on bank 2?? When I looked under the hood, I found a vacuum hose had come off going to the VSV valve, must have happened when I checked the air filter. Cleared the codes, test drove vehicle, problem fixed!! Make sure when replacing air filter to check all vacuum lines that are attached to the filter housing.
I changed my air filter and now I have the same issue. All 3 lights are are lit. Is there a way to reset them like you do the service light? I checked and all hoses are attached. How do you clear the codes?