'04 Civic, CVT, 50k miles

So yesterday everything is fine, driving home from work. Then the check engine light comes on. The car seems to be opperating completly normal and smooth. I make a note in my head to call the dealer for a service appointment. This morning on my way to work, I noticed my charge/assist lights aren't coming on, and the battery level is constant. I'm getting no power assist from the IMA, nor does it seem to recharge. My gas mileage went way down (36mpg ) since it has to do all the work of accelerating on the highway with just the ICE. 1 block from work, the IMA system kicked back in.

Now I did have time yesterday to stop by Advanced Auto, as they will hook up a scanner to pull codes, just to see what I'm in for. They pulled a P2000, which is the knock/o2 sensor circuit?

Anyone have similiar issues? What's the warrenty on these, I know they extended the warrenty of the CVTs to 70k, but is the rest of the powertrane still 36/36?

-Fadi

1991 Mazda Miata to beat Corvettes at the track
1999 Dodge Ram to climb through rocks and brush
2004 Honda Civic Hybrid to make up for the other 2