No, because it only simulates a very small part of reality. For example it could never estimate the weather for the next 2 hours by looking at a formation of heavy clouds.
By doing so we may check for complex cross connections and gain new insights. Actually I vividly remember waking up from dreams and suddenly realizing that I have a crush on a girl. I didn't really the day before (or was not aware of it) but during dreaming my brain seemed to say "I've checked all information that we have about this specimen and my simulations so far look promising!"
I sometimes also dream of deceased persons. The brain maybe again and again tries to make sense of this deeply unsettling experience and to somehow integrate that unexplainable into the simulation.
(BTW sorry for misspelling consciousness all the time in my post above - it was a little too late here)