how do you reset a ECU on a 2000 Maxima

I have a 2000 Maxima SE-V6 with 54,000 miles. After a recent snow storm and some bad roads, my air intake rattled apart at a joint. I put it
back together but my Check engine light has been on since. How can I
reset the computer myself?

Also the dealer has changed my rear o2 sensor once under warranty and I always have used premium fuel.