2009HHRCalifornia

Hi I just bought this beautiful used 2009 HHR LT with 28,000 miles almost 2 months ago. Still under warranty and I also got an extended.

Last week I had to use the back gate or the trunk for some reason. Later that evening when it got dark I noticed that the interior lights were still on and I tracked it that the back gate was ajar and had been this way for perhaps 9 hours. I closed it up, the car started up just fine and I went driving and did quick little stops here and there for about 20 min. I brought it back and parked it back in the garage. A few days later went out there to drive it and the interior lights work just fine but, when I turn the ignition on, all the lights come on the information dashboard etc. and the message says service call ECR Traction. It tries to click on but, will not start, you can hear a noise in the engine like a click. I called the chevyusa for it to be started or if needed a tow. Can anyone tell me what it might be ahead of time? I just do not want them to say oh your battery was losing power or something like that and just not follow up on the true error message of ECR Traction. Any ideas you have would be great. By the way this is my 2nd HHR and I am in love with the HHR. Mine is a metallic blue imperial. Thank you for your time!