Trac Control Light/Check Engine

[bud4ya]

I have a 99 Avalon XLS and the check engine light came on a couple of days ago. The code read P0420 which is something with Cat's. Has anyone gotten this code and found that replacing the O2 sensor before or after the cat took care of the check engine light? Or when that code comes up is it probally the cat itself?

2nd question is the light for the trac control came on today. Any idea what the issue could be with that? I did a search uner "trac control light" and nothing came up explaining what it could be.

Thanks

[yspert]

replace the cat. the other light comes on to get your attention. yspert