Discconect the battery for a few minutes, clean both terminals and the ground at the fender from the negative cable. After reconnected try to start; If you get two attempts ( car usually starts for 2 seconds then stops) after that you can not even get the starter to engage you have a problem with the SKREEM module. Use the search box for SKREEM, all kinds of info, but in a nut shell you will need to purchase a replacement from needswings.com about $700. There are a couple other sites that can attempt a repair of the module. You can find them in the threads on the SKREEM problems.

The other possablity is a problem with the RCM Relay Control Module. But it will give a little different start problem than what you have described. Please follow the info in the first paragraph then let us know exactly what happened.