WHAT DOES THE THREE RED FASHING ;LIGHTS MEAN?

The three red lights, or Red Ring of Death, is a very feared problem with Xbox 360 consoles.

It's a very serious issue that sometimes requires hard drive replacement--if it's still within warranty, call Microsoft.

Your system needs an x-clamp replacement. cause cpu or gpu has to be reflowed. this is your cause. i have been fixing this problem for over 2 years