I have a 2006 Jetta TDI. It has set a lot, but I start it occasionally. I was thinking of selling it and a guy was supposed to come look at it tomorrow so I thought I would start it up and let ti run. Well, had the Immobilizer light on and will not run. Starts and shuts down. I checked the battery, charged it a bit without cables on, still will not run. Original key and all. The battery was not dead but low. So, what could have caused this to happen, and what to do. I live over 300 miles from a dealer. I am on my own on this so need help.