The system would be green for a few minutes when first starting the car, then turn red. The user guide for the car said it is only red for a hardware malfunction. A VW dealership and the Car-Net customer service folks both seemed confused when I first said the light was red, as if they didn't know it could do that. It was later found to be a faulty wire in the roof where it connected to the antenna. After the wire was replaced, the light remains green. I've been told by Car-Net, the light can also be red if you are not signed up for the service. I imagine this issue could be severe if in the event of an emergency, the system fails to connect you to help.