2007 yukon xl battery dead recharged battery will not start no security light no gages work when you turn the key on. try to start the engine nothing happen like the security system shut down. can you please assist?

We had the same issue with our 2007 Yukon Denali XL. Died on us twice after sitting for short periods of time; once we watched a DVD with the engine off and battery died within 10 minutes. The dealership kept it overnight to troubleshoot why the battery died so quickly. They said the radio was "pulling" too much from the battery. (They supposably fixed it) But again a few days later the battery died again after sitting overnight. We brought it back to the dealership and they brought in a GMC "expert" to replace the entire DVD/CD/Navigation system. They also replaced our battery with a much larger battery, similar to the ones that GMC puts in there diesel trucks. They had our Denali for 5 days, but it appears to be fixed now.
Getting it fixed correctly wasn't without headaches, but it was all covered under warranty, including the battery. And they are updating the nav w/ the new edition disc as well for no charge.