Thanks Steve for your reply.

When i filled up my gas, the "Cruise Range" is normally 10 to 15 miles. I never got it down to 0 before. So basically you are saying that if the cruise range goes down to 0, it's still safe to continue to drive? I was afraid that if the cruise range goes down to 0, I'll run out of gas in middle of freeway. I did that once with my Honda Civic Hybrid back in 2004. So that means the "Cruise Range" is not accurate, since I still have about 3 gallons left on my gas tank...