I am new to this forum so thanks in advance for any help. Anyway I have a 09 CTS4 that was purchased a couple months ago. Everything was working great until I left my radar detector plugged in and ran the battery down. After hooking a booster to it I could not get it to attempt to start. I know battery is now charged as I also tried new battery in it. Have undone cables to try and reset also. Here are issue: It has RKE. Key fobs do not work, front doors are locked from outside but you can reach thru front window and open from inside, trunk release button on door does not work, everything powers up but error messages for service all wheel drive and service ac pop up in DIC. I have undone both ECM harnesses to check them. Checked all fuses under the hood. Any ideas on correcting the issue? Thanks