The Check Engine Light may illuminate due to an O2 sensor heater fault. Most commonly the affected O2 sensor will need to be replaced to correct this concern.Google+
Car Problem Reports
Lexus ES330 Check Engine LIght With Code P0135, P0141, P0155, or P0161
Lexus ES330 Problem
Visitor, 2004 Lexus ES330, 147,000 mi
Replaced both O2 sensors and still have check engine light. Was told to replace MAF, did that and now told to replace air fuel sensor and spark plugs. I hope it works.
Visitor, 2004 Lexus ES330
I changed the O2 sensor as it was asking but after I did so the light came back on and now it's reading codes pertaining to the catalytic converter do I just drive the car till it passed inspection