The twilight Sentinel in my car doesnt work and hasnt sicne i boight it this summer. i havent really been worried about it as the car needed other things that were more important. But now that everything is good with the car, im interested in fixing it. Now, what are some things i should look at or do in order to find the problem?> i really have no idea how the system works, so any info would be helpful, like are there any common solutions to it not working???