I have that code right now too. The dealer I bought the truck from cheated the computer by placing a spacer on the second sensor after the cat so the CEL would not come on. I found this out by taking the truck in for timing belt replacement at a Toyota specialty shop who pointed it out to me right away. Unreal! They took the spacer out and gave it to me. I feel like I should report it to the DMV. Anyways the specialty shop said they cleaned the cat by heating it up and put the sensor back into the exhaust the way it was supposed to be. They told me the CEL may or may not come on again after the cat cleaning. If it does, they suggested going after the dealer for the replacement of the cat (good luck with that one!). They documented the spacer being removed on my bill. BTW, The Toyota specialty shop was great. Their called Rons Toy Shop in Manchester NH. They went through the truck and only performed maintenance on what they thought it needed. This included the timing belt, water pump, serp belt, thermostat, gaskets, seals, coolant, spark plugs, PCV, oil change, sway bar bushings and alignment. They did NOT charge me for cleaning the cat, lubing the steering shaft u joint, greased the drive train, inspected all fluids, brakes, and joints, and even replaced the plastic film covering my instrument panel on the dashboard (looks like new again). total bill was 1,096. The Toyota dealer wanted 750 for just the timing belt and water pump and I am sure they would have not gone through the truck like Rons did, so I feel better about having the service done.